meson: switch minimum meson version to 0.58.2, minimum recommended to 0.59.2

Meson 0.58.2 does not need b_staticpic=$pie anymore, and has
stabilized the keyval module.  Remove the workaround and use a few
replacements for features deprecated in the 0.57.0 release cycle.

One feature that we would like to use is passing dependencies to
summary.  However, that was broken in 0.59.0 and 0.59.1.  Therefore,
use the embedded Meson if the host has anything older than 0.59.2,
but allow --meson= to use 0.58.2.

Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff --git a/meson.build b/meson.build
index 60f4f45..17e77fe 100644
--- a/meson.build
+++ b/meson.build
@@ -1,14 +1,10 @@
-project('qemu', ['c'], meson_version: '>=0.55.0',
-        default_options: ['warning_level=1', 'c_std=gnu11', 'cpp_std=gnu++11', 'b_colorout=auto'] +
-                         (meson.version().version_compare('>=0.56.0') ? [ 'b_staticpic=false' ] : []),
-        version: run_command('head', meson.source_root() / 'VERSION').stdout().strip())
+project('qemu', ['c'], meson_version: '>=0.58.2',
+        default_options: ['warning_level=1', 'c_std=gnu11', 'cpp_std=gnu++11', 'b_colorout=auto',
+                          'b_staticpic=false'],
+        version: files('VERSION'))
 
 not_found = dependency('', required: false)
-if meson.version().version_compare('>=0.56.0')
-  keyval = import('keyval')
-else
-  keyval = import('unstable-keyval')
-endif
+keyval = import('keyval')
 ss = import('sourceset')
 fs = import('fs')
 
@@ -1972,21 +1968,21 @@
 hxtool = find_program('scripts/hxtool')
 shaderinclude = find_program('scripts/shaderinclude.pl')
 qapi_gen = find_program('scripts/qapi-gen.py')
-qapi_gen_depends = [ meson.source_root() / 'scripts/qapi/__init__.py',
-                     meson.source_root() / 'scripts/qapi/commands.py',
-                     meson.source_root() / 'scripts/qapi/common.py',
-                     meson.source_root() / 'scripts/qapi/error.py',
-                     meson.source_root() / 'scripts/qapi/events.py',
-                     meson.source_root() / 'scripts/qapi/expr.py',
-                     meson.source_root() / 'scripts/qapi/gen.py',
-                     meson.source_root() / 'scripts/qapi/introspect.py',
-                     meson.source_root() / 'scripts/qapi/parser.py',
-                     meson.source_root() / 'scripts/qapi/schema.py',
-                     meson.source_root() / 'scripts/qapi/source.py',
-                     meson.source_root() / 'scripts/qapi/types.py',
-                     meson.source_root() / 'scripts/qapi/visit.py',
-                     meson.source_root() / 'scripts/qapi/common.py',
-                     meson.source_root() / 'scripts/qapi-gen.py'
+qapi_gen_depends = [ meson.current_source_dir() / 'scripts/qapi/__init__.py',
+                     meson.current_source_dir() / 'scripts/qapi/commands.py',
+                     meson.current_source_dir() / 'scripts/qapi/common.py',
+                     meson.current_source_dir() / 'scripts/qapi/error.py',
+                     meson.current_source_dir() / 'scripts/qapi/events.py',
+                     meson.current_source_dir() / 'scripts/qapi/expr.py',
+                     meson.current_source_dir() / 'scripts/qapi/gen.py',
+                     meson.current_source_dir() / 'scripts/qapi/introspect.py',
+                     meson.current_source_dir() / 'scripts/qapi/parser.py',
+                     meson.current_source_dir() / 'scripts/qapi/schema.py',
+                     meson.current_source_dir() / 'scripts/qapi/source.py',
+                     meson.current_source_dir() / 'scripts/qapi/types.py',
+                     meson.current_source_dir() / 'scripts/qapi/visit.py',
+                     meson.current_source_dir() / 'scripts/qapi/common.py',
+                     meson.current_source_dir() / 'scripts/qapi-gen.py'
 ]
 
 tracetool = [
@@ -2635,14 +2631,14 @@
   if target.endswith('-softmmu')
     execs = [{
       'name': 'qemu-system-' + target_name,
-      'gui': false,
+      'win_subsystem': 'console',
       'sources': files('softmmu/main.c'),
       'dependencies': []
     }]
     if targetos == 'windows' and (sdl.found() or gtk.found())
       execs += [{
         'name': 'qemu-system-' + target_name + 'w',
-        'gui': true,
+        'win_subsystem': 'windows',
         'sources': files('softmmu/main.c'),
         'dependencies': []
       }]
@@ -2651,7 +2647,7 @@
       specific_fuzz = specific_fuzz_ss.apply(config_target, strict: false)
       execs += [{
         'name': 'qemu-fuzz-' + target_name,
-        'gui': false,
+        'win_subsystem': 'console',
         'sources': specific_fuzz.sources(),
         'dependencies': specific_fuzz.dependencies(),
       }]
@@ -2659,7 +2655,7 @@
   else
     execs = [{
       'name': 'qemu-' + target_name,
-      'gui': false,
+      'win_subsystem': 'console',
       'sources': [],
       'dependencies': []
     }]
@@ -2678,7 +2674,7 @@
                link_language: link_language,
                link_depends: [block_syms, qemu_syms] + exe.get('link_depends', []),
                link_args: link_args,
-               gui_app: exe['gui'])
+               win_subsystem: exe['win_subsystem'])
 
     if targetos == 'darwin'
       icon = 'pc-bios/qemu.rsrc'