virtio-blk: free vblk-vqs in error path of virtblk_probe()

stable inclusion
from linux-4.19.132
commit a8c7823274e608903f8d72d72d18e6a4aee45c83

--------------------------------

[ Upstream commit e7eea44e ]

Else there will be memory leak if alloc_disk() fails.

Fixes: 6a27b656 ("block: virtio-blk: support multi virt queues per virtio-blk device")
Signed-off-by: Hou Tao <houtao1@huawei.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>