cifs: use the NUM_AUTHS and NUM_SUBAUTHS constants in cifsacl code

...instead of hardcoding in '5' and '6' all over the place.

Reviewed-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>

fs/cifs/cifsacl.h

@@ -60,8 +60,8 @@ struct cifs_ntsd {
 struct cifs_sid {
 	__u8 revision; /* revision level */
 	__u8 num_subauth;
-	__u8 authority[6];
-	__le32 sub_auth[5]; /* sub_auth[num_subauth] */
+	__u8 authority[NUM_AUTHS];
+	__le32 sub_auth[NUM_SUBAUTHS]; /* sub_auth[num_subauth] */
 } __attribute__((packed));
 
 struct cifs_acl {