modify route priority for /32 src route (#5832)

Signed-off-by: Mengxin Liu <liumengxinfly@gmail.com>

Author: oilbeater

dist/images/patches/9ee66bd91be65605cffb9a490b4dba3bc13358e9.patch

@@ -21,7 +21,7 @@ index cf9d2217ae..c530468ec2 100644
 +    if (is_src_route) {
 +        *priority = 1;
 +        if ((is_ipv4 && plen == 32) || (plen == 128)) {
-+            *priority = 2;
++            *priority = ROUTE_PRIO_OFFSET_STATIC + 1;
 +        }
 +    } else {
 +        *priority = (plen * ROUTE_PRIO_OFFSET_MULTIPLIER) + ofs;