meson: require 0.61.3

This removes the dependency of dbus-display on --enable-modules.  It also allows
cleanups in modinfo collection and allows moving C++ compiler detection to
meson.build.

Because it is now deprecated to use install_subdir to create an empty directory,
replace it with install_emptydir.

Updating the Meson submodule to 0.61.5 also removes the message

    WARNING: Broken python installation detected. Python files installed
    by Meson might not be found by python interpreter.

unless using system meson is forced with --meson.

Resolves: https://gitlab.com/qemu-project/qemu/-/issues/873
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/848
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

configure

@@ -1114,7 +1114,7 @@ fi
 python="$python -B"
 
 if test -z "$meson"; then
-    if test "$explicit_python" = no && has meson && version_ge "$(meson --version)" 0.59.3; then
+    if test "$explicit_python" = no && has meson && version_ge "$(meson --version)" 0.61.5; then
         meson=meson
     elif test "$git_submodules_action" != 'ignore' ; then
         meson=git

meson

@@ -1 +1 @@
-Subproject commit 12f9f04ba0decfda425dbbf9a501084c153a2d18
+Subproject commit 3a9b285a55b91b53b2acda987192274352ecb5be

meson.build

@@ -1,4 +1,4 @@
-project('qemu', ['c'], meson_version: '>=0.59.3',
+project('qemu', ['c'], meson_version: '>=0.61.3',
         default_options: ['warning_level=1', 'c_std=gnu11', 'cpp_std=gnu++11', 'b_colorout=auto',
                           'b_staticpic=false', 'stdsplit=false', 'optimization=2', 'b_pie=true'],
         version: files('VERSION'))
@@ -1674,12 +1674,9 @@ endif
 have_host_block_device = (targetos != 'darwin' or
     cc.has_header('IOKit/storage/IOMedia.h'))
 
-# FIXME enable_modules shouldn't be necessary, but: https://github.com/mesonbuild/meson/issues/8333
 dbus_display = get_option('dbus_display') \
   .require(gio.version().version_compare('>=2.64'),
            error_message: '-display dbus requires glib>=2.64') \
-  .require(enable_modules,
-           error_message: '-display dbus requires --enable-modules') \
   .require(gdbus_codegen.found(),
            error_message: gdbus_codegen_error.format('-display dbus')) \
   .require(opengl.found() and gbm.found(),

qga/meson.build

@@ -138,7 +138,7 @@ else
   if get_option('guest_agent_msi').enabled()
     error('MSI guest agent package is available only for MinGW Windows cross-compilation')
   endif
-  install_subdir('run', install_dir: get_option('localstatedir'))
+  install_emptydir(get_option('localstatedir') / 'run')
 endif
 
 alias_target('qemu-ga', all_qga)