Use project arguments for HAVE_X11 and HAVE_WAYLAND

This means you don't have to use explicit compiler_args for
cpp.preprocess which then means the meson requirement can be lowered.

Signed-off-by: Alfred Wingate <parona@protonmail.com>

Author: parona-source

meson.build

@@ -2,7 +2,7 @@ project('MangoHud',
   ['c', 'cpp'],
   version : 'v0.8.1',
   license : 'MIT',
-  meson_version: '>=1.3.2',
+  meson_version: '>=0.64.0',
   default_options : ['buildtype=release', 'c_std=c99', 'cpp_std=c++17', 'warning_level=2']
 )
 

src/meson.build

@@ -146,7 +146,7 @@ if is_unixy
   endif
 
   if get_option('with_x11').enabled()
-    pre_args += '-DHAVE_X11'
+    add_project_arguments('-DHAVE_X11', language : ['c', 'cpp'])
 
     vklayer_files += files(
       'loaders/loader_x11.cpp',
@@ -160,7 +160,7 @@ if is_unixy
   endif
 
   if get_option('with_wayland').enabled()
-    pre_args += '-DHAVE_WAYLAND'
+    add_project_arguments('-DHAVE_WAYLAND', language : ['c', 'cpp'])
 
     vklayer_files += files(
       'wayland_keybinds.cpp'
@@ -240,10 +240,7 @@ mangohud_shared_lib = shared_library(
 )
 
 if is_unixy
-  mangohud_opengl_versionscript = cpp.preprocess(
-    'mangohud_opengl.version',
-    compile_args: pre_args,
-  )
+  mangohud_opengl_versionscript = cpp.preprocess('mangohud_opengl.version')
 
   mangohud_opengl_shared_lib = shared_library(
     'MangoHud_opengl',