mtip32xx: release the semaphore on an error path

Release the semaphore in an error path in mtip_hw_get_scatterlist(). This
fixes the smatch warning inconsistent returns.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Asai Thambi S P <asamymuthupa@micron.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>