[S390] constify function pointer tables.

Signed-off-by: Jan Engelhardt <jengelh@computergmbh.de>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/drivers/s390/char/tape_proc.c b/drivers/s390/char/tape_proc.c
index cea49f0..c9b96d5 100644
--- a/drivers/s390/char/tape_proc.c
+++ b/drivers/s390/char/tape_proc.c
@@ -97,7 +97,7 @@
 {
 }
 
-static struct seq_operations tape_proc_seq = {
+static const struct seq_operations tape_proc_seq = {
 	.start		= tape_proc_start,
 	.next		= tape_proc_next,
 	.stop		= tape_proc_stop,