meson: inline PROJECT_NAME in mangohud.json.in

Signed-off-by: Emil Velikov <emil.velikov@collabora.com>

src/mangohud.json.in

@@ -1,7 +1,7 @@
 {
     "file_format_version" : "1.0.0",
     "layer" : {
-      "name": "VK_LAYER_@PROJECT_NAME@_overlay",
+      "name": "VK_LAYER_MANGOHUD_overlay",
       "type": "GLOBAL",
       "api_version": "1.3.0",
       "library_path": "@ld_libdir_mangohud@libMangoHud.so",

src/meson.build

@@ -289,8 +289,7 @@ endif
 
 configure_file(input : 'mangohud.json.in',
   output : '@0@.json'.format(meson.project_name()),
-  configuration : {'ld_libdir_mangohud' : ld_libdir_mangohud_vk.replace('\$', '$'),
-                  'PROJECT_NAME' : meson.project_name().to_upper()},
+  configuration : {'ld_libdir_mangohud' : ld_libdir_mangohud_vk.replace('\$', '$')},
   install : true,
   install_dir : join_paths(get_option('datadir'), 'vulkan', 'implicit_layer.d'),
   install_tag : 'runtime',