Revert "meson.build: default to -gsplit-dwarf for debug info"

This reverts commit 563b1a35ed1f1151505d4fe5f723827d1b3fd4bc.

Split debug info support is broken when cross compiling
(https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99973).  People
that would like to use it can add it via --extra-cflags.

Reported-by: Konstantin Kostiuk <kkostiuk@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

meson.build

@@ -604,10 +604,6 @@ if get_option('tsan')
   qemu_ldflags = ['-fsanitize=thread'] + qemu_ldflags
 endif
 
-if get_option('debug') and get_option('split_debug')
-  qemu_cflags += '-gsplit-dwarf'
-endif
-
 # Detect support for PT_GNU_RELRO + DT_BIND_NOW.
 # The combination is known as "full relro", because .got.plt is read-only too.
 qemu_ldflags += cc.get_supported_link_arguments('-Wl,-z,relro', '-Wl,-z,now')
@@ -4599,8 +4595,6 @@ if have_rust
   summary_info += {'bindgen':         bindgen.full_path()}
   summary_info += {'bindgen version': bindgen.version()}
 endif
-# option_cflags is purely for the summary display, meson will pass
-# -g/-O options directly
 option_cflags = (get_option('debug') ? ['-g'] : [])
 if get_option('optimization') != 'plain'
   option_cflags += ['-O' + get_option('optimization')]

meson_options.txt

@@ -362,8 +362,6 @@ option('debug_mutex', type: 'boolean', value: false,
        description: 'mutex debugging support')
 option('debug_stack_usage', type: 'boolean', value: false,
        description: 'measure coroutine stack usage')
-option('split_debug', type: 'boolean', value: true,
-       description: 'split debug info from object files')
 option('qom_cast_debug', type: 'boolean', value: true,
        description: 'cast debugging support')
 option('slirp_smbd', type : 'feature', value : 'auto',

scripts/meson-buildoptions.sh

@@ -504,8 +504,6 @@ _meson_option_parse() {
     --disable-strict-rust-lints) printf "%s" -Dstrict_rust_lints=false ;;
     --enable-strip) printf "%s" -Dstrip=true ;;
     --disable-strip) printf "%s" -Dstrip=false ;;
-    --enable-split-debug) printf "%s" -Dsplit_debug=true ;;
-    --disable-split-debug) printf "%s" -Dsplit_debug=false ;;
     --sysconfdir=*) quote_sh "-Dsysconfdir=$2" ;;
     --enable-tcg) printf "%s" -Dtcg=enabled ;;
     --disable-tcg) printf "%s" -Dtcg=disabled ;;