block/rnbd-clt: fix CHECK:BRACES warning

This patch fix the "CHECK:BRACES: braces {} should be used on all
arms of this statement" warning from checkpatch

Signed-off-by: Gioh Kim <gi-oh.kim@ionos.com>
Signed-off-by: Md Haris Iqbal <haris.iqbal@ionos.com>
Link: https://lore.kernel.org/r/20220114155855.984144-2-haris.iqbal@ionos.com


Signed-off-by: Jens Axboe <axboe@kernel.dk>