[S390] Get rid of a lot of sparse warnings.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/drivers/s390/crypto/zcrypt_pcixcc.c b/drivers/s390/crypto/zcrypt_pcixcc.c
index b7153c1..252443b 100644
--- a/drivers/s390/crypto/zcrypt_pcixcc.c
+++ b/drivers/s390/crypto/zcrypt_pcixcc.c
@@ -709,7 +709,8 @@
  *	  PCIXCC/CEX2C device to the request distributor
  * @xcRB: pointer to the send_cprb request buffer
  */
-long zcrypt_pcixcc_send_cprb(struct zcrypt_device *zdev, struct ica_xcRB *xcRB)
+static long zcrypt_pcixcc_send_cprb(struct zcrypt_device *zdev,
+				    struct ica_xcRB *xcRB)
 {
 	struct ap_message ap_msg;
 	struct response_type resp_type = {