drm/i915: fix open-coded DIV_ROUND_UP

Use the nice Kernel macro, it makes the code much more readable.
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: NJani Nikula <jani.nikula@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/i915_gem.c

@@ -261,7 +261,7 @@ i915_gem_dumb_create(struct drm_file *file,
 		     struct drm_mode_create_dumb *args)
 {
 	/* have to work out size/pitch and return them */
-	args->pitch = ALIGN(args->width * ((args->bpp + 7) / 8), 64);
+	args->pitch = ALIGN(args->width * DIV_ROUND_UP(args->bpp, 8), 64);
 	args->size = args->pitch * args->height;
 	return i915_gem_create(file, dev,
 			       args->size, &args->handle);

drivers/gpu/drm/i915/intel_fbdev.c

@@ -78,8 +78,8 @@ static int intelfb_create(struct drm_fb_helper *helper,
 	mode_cmd.width = sizes->surface_width;
 	mode_cmd.height = sizes->surface_height;
 
-	mode_cmd.pitches[0] = ALIGN(mode_cmd.width * ((sizes->surface_bpp + 7) /
-						      8), 64);
+	mode_cmd.pitches[0] = ALIGN(mode_cmd.width *
+				    DIV_ROUND_UP(sizes->surface_bpp, 8), 64);
 	mode_cmd.pixel_format = drm_mode_legacy_fb_format(sizes->surface_bpp,
 							  sizes->surface_depth);