drm: Replace drm_format_num_planes() with fb->format->num_planes

Replace drm_format_num_planes(fb->pixel_format) with just
fb->format->num_planes. Avoids the expensive format info lookup.

@@
struct drm_framebuffer *a;
struct drm_framebuffer b;
@@
(
- drm_format_num_planes(a->pixel_format)
+ a->format->num_planes
|
- drm_format_num_planes(b.pixel_format)
+ b.format->num_planes
)

@@
struct drm_plane_state *a;
struct drm_plane_state b;
@@
(
- drm_format_num_planes(a->fb->pixel_format)
+ a->fb->format->num_planes
|
- drm_format_num_planes(b.fb->pixel_format)
+ b.fb->format->num_planes
)

@@
struct drm_framebuffer *a;
identifier T;
@@
  T = a->pixel_format
<+...
- drm_format_num_planes(T)
+ a->format->num_planes
...+>

@@
struct drm_framebuffer b;
identifier T;
@@
  T = b.pixel_format
<+...
- drm_format_num_planes(T)
+ b.format->num_planes
...+>

v2: Rerun spatch due to code changes

Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Suggested-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1481751022-18015-1-git-send-email-ville.syrjala@linux.intel.com

drivers/gpu/drm/tegra/dc.c

@@ -531,7 +531,7 @@ static int tegra_plane_atomic_check(struct drm_plane *plane,
 	 * error out if the user tries to display a framebuffer with such a
 	 * configuration.
 	 */
-	if (drm_format_num_planes(state->fb->pixel_format) > 2) {
+	if (state->fb->format->num_planes > 2) {
 		if (state->fb->pitches[2] != state->fb->pitches[1]) {
 			DRM_ERROR("unsupported UV-plane configuration\n");
 			return -EINVAL;
@@ -576,7 +576,7 @@ static void tegra_plane_atomic_update(struct drm_plane *plane,
 	window.format = state->format;
 	window.swap = state->swap;
 
-	for (i = 0; i < drm_format_num_planes(fb->pixel_format); i++) {
+	for (i = 0; i < fb->format->num_planes; i++) {
 		struct tegra_bo *bo = tegra_fb_get_plane(fb, i);
 
 		window.base[i] = bo->paddr + fb->offsets[i];