staging: ccree: use signal safe completion wait

We were waiting for a completion notification of HW DMA
operation using an interruptible wait which can result
in data corruption if a signal interrupted us while
DMA was not yet completed.

Fix this by moving to uninterrupted wait.

Fixes: abefd674 ("staging: ccree: introduce CryptoCell HW driver").
Signed-off-by: Gilad Ben-Yossef <gilad@benyossef.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/ccree/ssi_request_mgr.c

@@ -382,7 +382,8 @@ int send_request(
 		/* Wait upon sequence completion.
 		 *  Return "0" -Operation done successfully.
 		 */
-		return wait_for_completion_interruptible(&ssi_req->seq_compl);
+		wait_for_completion(&ssi_req->seq_compl);
+		return 0;
 	} else {
 		/* Operation still in process */
 		return -EINPROGRESS;