disas: Enable capstone disassembly for s390x

Enable s390x, aka SYSZ, in the git submodule build.
Set the capstone parameters for both s390x host and guest.

Tested-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Acked-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
diff --git a/disas.c b/disas.c
index 9dfbeed..7c18d7d 100644
--- a/disas.c
+++ b/disas.c
@@ -203,6 +203,9 @@
     s->info.print_insn = print_insn_m68k;
 #elif defined(__s390__)
     s->info.print_insn = print_insn_s390;
+    s->info.cap_arch = CS_ARCH_SYSZ;
+    s->info.cap_insn_unit = 2;
+    s->info.cap_insn_split = 6;
 #elif defined(__hppa__)
     s->info.print_insn = print_insn_hppa;
 #endif