tcmu: fix error return code in tcmu_configure_device()

Fix to return error code -ENOMEM from the kzalloc() error handling
case instead of 0, as done elsewhere in this function.

Fixes: 80eb876 ("tcmu: allow max block and global max blocks to be settable")
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Acked-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

drivers/target/target_core_user.c

@@ -1675,8 +1675,10 @@ static int tcmu_configure_device(struct se_device *dev)
 
 	udev->data_bitmap = kzalloc(BITS_TO_LONGS(udev->max_blocks) *
 				    sizeof(unsigned long), GFP_KERNEL);
-	if (!udev->data_bitmap)
+	if (!udev->data_bitmap) {
+		ret = -ENOMEM;
 		goto err_bitmap_alloc;
+	}
 
 	udev->mb_addr = vzalloc(CMDR_SIZE);
 	if (!udev->mb_addr) {