drm/armada: remove some dead code

'dma_buf_map_attachment()' can not return NULL, so there is no need to
check for it.

Also add a space in order to improve layout.
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

drivers/gpu/drm/armada/armada_gem.c

@@ -594,11 +594,7 @@ int armada_gem_map_import(struct armada_gem_object *dobj)
 	int ret;
 
 	dobj->sgt = dma_buf_map_attachment(dobj->obj.import_attach,
-					  DMA_TO_DEVICE);
-	if (!dobj->sgt) {
-		DRM_ERROR("dma_buf_map_attachment() returned NULL\n");
-		return -EINVAL;
-	}
+					   DMA_TO_DEVICE);
 	if (IS_ERR(dobj->sgt)) {
 		ret = PTR_ERR(dobj->sgt);
 		dobj->sgt = NULL;