NFSD: Add missing comment of "expiry" in expkey_parse()

Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
diff --git a/fs/nfsd/export.c b/fs/nfsd/export.c
index 858c536..263d30e 100644
--- a/fs/nfsd/export.c
+++ b/fs/nfsd/export.c
@@ -68,7 +68,7 @@
 
 static int expkey_parse(struct cache_detail *cd, char *mesg, int mlen)
 {
-	/* client fsidtype fsid [path] */
+	/* client fsidtype fsid expiry [path] */
 	char *buf;
 	int len;
 	struct auth_domain *dom = NULL;