Hmm...  Looks like a unified diff to me...
The text leading up to this was:
--------------------------
|--- a/sys/dev/drm/radeon/radeon_combios.c
|+++ b/sys/dev/drm/radeon/radeon_combios.c
--------------------------
Patching file sys/dev/drm/radeon/radeon_combios.c using Plan A...
Hunk #1 succeeded at 2746.
done