drm/exynos: Add missing braces around sizeof

Fixes the following checkpatch warning:
WARNING: sizeof *sgt should be sizeof(*sgt)
Signed-off-by: NSachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: NInki Dae <inki.dae@samsung.com>

drivers/gpu/drm/exynos/exynos_drm_g2d.c

@@ -429,7 +429,7 @@ static dma_addr_t *g2d_userptr_get_dma_addr(struct drm_device *drm_dev,
 
 	g2d_userptr->pages = pages;
 
-	sgt = kzalloc(sizeof *sgt, GFP_KERNEL);
+	sgt = kzalloc(sizeof(*sgt), GFP_KERNEL);
 	if (!sgt) {
 		DRM_ERROR("failed to allocate sg table.\n");
 		ret = -ENOMEM;