renderer/native: Add API to get primary GPU

Will be used when acquiring scanouts from Wayland buffers.

Original Mutter commit: https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/798/diffs?commit_id=3dd8861fbf51183fd69106f55095d444cd37cc34

Author: Sunderland93

src/backends/native/meta-renderer-native.c

@@ -313,6 +313,12 @@ meta_gbm_device_from_gpu (MetaGpuKms *gpu_kms)
   return renderer_gpu_data->gbm.device;
 }
 
+MetaGpuKms *
+meta_renderer_native_get_primary_gpu (MetaRendererNative *renderer_native)
+{
+  return renderer_native->primary_gpu_kms;
+}
+
 static MetaRendererNativeGpuData *
 meta_create_renderer_native_gpu_data (MetaGpuKms *gpu_kms)
 {

src/backends/native/meta-renderer-native.h

@@ -51,6 +51,8 @@ MetaRendererNative * meta_renderer_native_new (MetaBackendNative  *backend_nativ
 
 struct gbm_device * meta_gbm_device_from_gpu (MetaGpuKms *gpu_kms);
 
+MetaGpuKms * meta_renderer_native_get_primary_gpu (MetaRendererNative *renderer_native);
+
 void meta_renderer_native_finish_frame (MetaRendererNative *renderer_native);
 
 int64_t meta_renderer_native_get_frame_counter (MetaRendererNative *renderer_native);