core.c: last attribute's enumerator cannot be greater than MAX_STD_ATTR

Raise a build error if the last attribute's enumarator (e.g.
_ZIO_BUF_ATTR_STD_NUM) is greater than the maximum numer of standard
attributes ZIO_MAX_STD_ATTR

Signed-off-by: Federico Vaga <federico.vaga@gmail.com>
Acked-by: Alessandro Rubini <rubini@gnudd.com>

core.c

@@ -83,6 +83,11 @@ static int __init zio_init(void)
 {
 	int err;
 
+	/* The standard attributes must be less than ZIO_MAX_STD_ATTR */
+	BUILD_BUG_ON(_ZIO_DEV_ATTR_STD_NUM > ZIO_MAX_STD_ATTR);
+	BUILD_BUG_ON(_ZIO_TRG_ATTR_STD_NUM > ZIO_MAX_STD_ATTR);
+	BUILD_BUG_ON(_ZIO_BUF_ATTR_STD_NUM > ZIO_MAX_STD_ATTR);
+
 	/* The attribute 'version' must be the last attributes */
 	BUILD_BUG_ON(_ZIO_DEV_ATTR_STD_NUM != ZIO_ATTR_VERSION + 1);
 	BUILD_BUG_ON(_ZIO_TRG_ATTR_STD_NUM != ZIO_ATTR_VERSION + 1);