radeonsi: Support PIPE_VIDEO_CAP_SKIP_CLEAR_SURFACE

Starting with .59 amdgpu now clears VRAM on allocation, so we don't
need to clear video buffers which are always allocated in VRAM.

Reviewed-by: Leo Liu <leo.liu@amd.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/31677>

src/gallium/drivers/radeonsi/si_get.c

@@ -1059,6 +1059,8 @@ static int si_get_video_param(struct pipe_screen *screen, enum pipe_video_profil
           sscreen->info.vcn_ip_version == VCN_4_0_3)
          return true;
       return false;
+   case PIPE_VIDEO_CAP_SKIP_CLEAR_SURFACE:
+      return sscreen->info.is_amdgpu && sscreen->info.drm_minor >= 59;
    default:
       return 0;
    }