crypto: zynqmp-sha - Add locking

[ Upstream commit c7e68043 ]

The hardwrae is only capable of one hash at a time, so add a lock
to make sure that it isn't used concurrently.

Fixes: 7ecc3e34 ("crypto: xilinx - Add Xilinx SHA3 driver")
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>