[mutter] renderer/native: store dumb FB format

[Ray Strode <halfline src gnome org>]

commit 8c4743ee2aea399806d1abd9e774658d763cb053
Author: Pekka Paalanen <pekka paalanen collabora co uk>
Date:   Fri Nov 9 14:22:18 2018 +0200

    renderer/native: store dumb FB format
    
    The format will be needed in a following commit in the CPU copy path
    which stops hardcoding another format and starts using the format the
    dumb FB was created with.

 src/backends/native/meta-renderer-native.c | 2 ++
 1 file changed, 2 insertions(+)
---
diff --git a/src/backends/native/meta-renderer-native.c b/src/backends/native/meta-renderer-native.c
index 13596d002..6b0d6d3b0 100644
--- a/src/backends/native/meta-renderer-native.c
+++ b/src/backends/native/meta-renderer-native.c
@@ -127,6 +127,7 @@ typedef struct _MetaDumbBuffer
   int width;
   int height;
   int stride_bytes;
+  uint32_t drm_format;
 } MetaDumbBuffer;
 
 typedef struct _MetaOnscreenNativeSecondaryGpuState
@@ -2311,6 +2312,7 @@ init_dumb_fb (MetaDumbBuffer  *dumb_fb,
   dumb_fb->width = width;
   dumb_fb->height = height;
   dumb_fb->stride_bytes = create_arg.pitch;
+  dumb_fb->drm_format = format;
 
   return TRUE;