[S390] replace remaining __FUNCTION__ occurrences

__FUNCTION__ is gcc-specific, use __func__

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
diff --git a/drivers/s390/char/tape_34xx.c b/drivers/s390/char/tape_34xx.c
index 5b47e9c..874adf3 100644
--- a/drivers/s390/char/tape_34xx.c
+++ b/drivers/s390/char/tape_34xx.c
@@ -394,7 +394,7 @@
 			return tape_34xx_erp_failed(request, -ENOSPC);
 		default:
 			PRINT_ERR("Invalid op in %s:%i\n",
-				  __FUNCTION__, __LINE__);
+				  __func__, __LINE__);
 			return tape_34xx_erp_failed(request, 0);
 		}
 	}