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

drivers/gpu/drm/vmwgfx/vmwgfx_ldu.c

@@ -97,7 +97,8 @@ static int vmw_ldu_commit_list(struct vmw_private *dev_priv)
 		fb = entry->base.crtc.primary->fb;
 
 		return vmw_kms_write_svga(dev_priv, w, h, fb->pitches[0],
-					  fb->bits_per_pixel, fb->depth);
+					  fb->bits_per_pixel,
+					  fb->format->depth);
 	}
 
 	if (!list_empty(&lds->active)) {
@@ -105,7 +106,7 @@ static int vmw_ldu_commit_list(struct vmw_private *dev_priv)
 		fb = entry->base.crtc.primary->fb;
 
 		vmw_kms_write_svga(dev_priv, fb->width, fb->height, fb->pitches[0],
-				   fb->bits_per_pixel, fb->depth);
+				   fb->bits_per_pixel, fb->format->depth);
 	}
 
 	/* Make sure we always show something. */