NFSD: make cache_detail structures const

Make these const as they are only getting passed to the function
cache_create_net having the argument as const.

Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
diff --git a/fs/nfsd/export.c b/fs/nfsd/export.c
index f9e7dd5..8ceb25a 100644
--- a/fs/nfsd/export.c
+++ b/fs/nfsd/export.c
@@ -232,7 +232,7 @@ static struct cache_head *expkey_alloc(void)
 		return NULL;
 }
 
-static struct cache_detail svc_expkey_cache_template = {
+static const struct cache_detail svc_expkey_cache_template = {
 	.owner		= THIS_MODULE,
 	.hash_size	= EXPKEY_HASHMAX,
 	.name		= "nfsd.fh",
@@ -748,7 +748,7 @@ static struct cache_head *svc_export_alloc(void)
 		return NULL;
 }
 
-static struct cache_detail svc_export_cache_template = {
+static const struct cache_detail svc_export_cache_template = {
 	.owner		= THIS_MODULE,
 	.hash_size	= EXPORT_HASHMAX,
 	.name		= "nfsd.export",