memory: cpu_physical_memory_set_dirty_range() always dirty all flags

So remove the flag argument and do it directly.  After this change,
there is nothing else using cpu_physical_memory_set_dirty_flags() so
remove it.

Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Orit Wasserman <owasserm@redhat.com>
diff --git a/exec.c b/exec.c
index ffda8be..f215960 100644
--- a/exec.c
+++ b/exec.c
@@ -1275,7 +1275,7 @@
                                        last_ram_offset() >> TARGET_PAGE_BITS);
     memset(ram_list.phys_dirty + (new_block->offset >> TARGET_PAGE_BITS),
            0, size >> TARGET_PAGE_BITS);
-    cpu_physical_memory_set_dirty_range(new_block->offset, size, 0xff);
+    cpu_physical_memory_set_dirty_range(new_block->offset, size);
 
     qemu_ram_setup_dump(new_block->host, size);
     qemu_madvise(new_block->host, size, QEMU_MADV_HUGEPAGE);