drm/ast: Remove useless drm_fb_get_bpp_depth() call

The function has no side effect and its returned values are ignored,
don't call it.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Eric Engestrom <eric.engestrom@imgtec.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1465236852-11710-1-git-send-email-laurent.pinchart@ideasonboard.com

drivers/gpu/drm/ast/ast_fb.c

@@ -167,12 +167,9 @@ static int astfb_create_object(struct ast_fbdev *afbdev,
 			       struct drm_gem_object **gobj_p)
 {
 	struct drm_device *dev = afbdev->helper.dev;
-	u32 bpp, depth;
 	u32 size;
 	struct drm_gem_object *gobj;
-
 	int ret = 0;
-	drm_fb_get_bpp_depth(mode_cmd->pixel_format, &depth, &bpp);
 
 	size = mode_cmd->pitches[0] * mode_cmd->height;
 	ret = ast_gem_create(dev, size, true, &gobj);