constify a bunch of struct file_operations instances

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/nfsd/nfsctl.c b/fs/nfsd/nfsctl.c
index f33455b..5bee031 100644
--- a/fs/nfsd/nfsctl.c
+++ b/fs/nfsd/nfsctl.c
@@ -177,7 +177,7 @@
 	return single_open(file, export_features_show, NULL);
 }
 
-static struct file_operations export_features_operations = {
+static const struct file_operations export_features_operations = {
 	.open		= export_features_open,
 	.read		= seq_read,
 	.llseek		= seq_lseek,
@@ -196,7 +196,7 @@
 	return single_open(file, supported_enctypes_show, NULL);
 }
 
-static struct file_operations supported_enctypes_ops = {
+static const struct file_operations supported_enctypes_ops = {
 	.open		= supported_enctypes_open,
 	.read		= seq_read,
 	.llseek		= seq_lseek,