drm: Nuke fb->depth

Replace uses of fb->depth with fb->format->depth. Less duplicate
information is a good thing.

@@
struct drm_framebuffer *fb;
expression E;
@@
 drm_helper_mode_fill_fb_struct(...) {
	...
-	fb->depth = E;
	...
 }

@@
struct nouveau_framebuffer *fb;
@@
- fb->base.depth
+ fb->base.format->depth

@@
struct drm_framebuffer fb;
@@
- fb.depth
+ fb.format->depth

@@
struct drm_framebuffer *fb;
@@
- fb->depth
+ fb->format->depth

@@
struct drm_framebuffer fb;
@@
- (fb.format->depth)
+ fb.format->depth

@@
struct drm_framebuffer *fb;
@@
- (fb->format->depth)
+ fb->format->depth

@@
@@
 struct drm_framebuffer {
	 ...
-	 unsigned int depth;
	 ...
 };

v2: Drop the vmw stuff (Daniel)
    Rerun spatch due to code changes

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1481751095-18249-1-git-send-email-ville.syrjala@linux.intel.com
diff --git a/drivers/gpu/drm/mgag200/mgag200_mode.c b/drivers/gpu/drm/mgag200/mgag200_mode.c
index 34dd38e..9399099 100644
--- a/drivers/gpu/drm/mgag200/mgag200_mode.c
+++ b/drivers/gpu/drm/mgag200/mgag200_mode.c
@@ -39,10 +39,10 @@ static void mga_crtc_load_lut(struct drm_crtc *crtc)
 	WREG8(DAC_INDEX + MGA1064_INDEX, 0);
 
 	if (fb && fb->bits_per_pixel == 16) {
-		int inc = (fb->depth == 15) ? 8 : 4;
+		int inc = (fb->format->depth == 15) ? 8 : 4;
 		u8 r, b;
 		for (i = 0; i < MGAG200_LUT_SIZE; i += inc) {
-			if (fb->depth == 16) {
+			if (fb->format->depth == 16) {
 				if (i > (MGAG200_LUT_SIZE >> 1)) {
 					r = b = 0;
 				} else {
@@ -947,7 +947,7 @@ static int mga_crtc_mode_set(struct drm_crtc *crtc,
 		dacvalue[MGA1064_MUL_CTL] = MGA1064_MUL_CTL_8bits;
 		break;
 	case 16:
-		if (fb->depth == 15)
+		if (fb->format->depth == 15)
 			dacvalue[MGA1064_MUL_CTL] = MGA1064_MUL_CTL_15bits;
 		else
 			dacvalue[MGA1064_MUL_CTL] = MGA1064_MUL_CTL_16bits;