qemu-img: improve queue depth validation in img_bench

This error was discovered by fuzzing qemu-img.

Currently, running `qemu-img bench -d 0` in img_bench is allowed,
which is a pointless operation and causes qemu-img to hang.

Signed-off-by: Denis Rastyogin <gerben@altlinux.org>
Message-ID: <20250327162423.25154-5-gerben@altlinux.org>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
1 file changed