Fix not rules for OPTn network case

Reported in forum https://forum.pfsense.org/index.php?topic=82319.0
The "if (is_subnet($src)) ... filter_address_add_vips_subnets" code needs to go outside all of the if that checks for opt interfaces (not just in the else part). That makes filter_address_add_vips_subnets get called in all cases, including when optn network is specified. (line 2264, 2265)
Then filter_address_add_vips_subnets needs to process the "not" code early, before checking if there are any VIPs (which was causing the routine to exit early in simple cases) - lines 2093-2100 chunk. This should also fix cases of using "LANnet", "WANnet" and "not" in rules on an interface that has just a plain address (no VIPs).
Lines 2144 and 2158 are no functional change. The formatting of the multi-line statement was odd, so I put it back all on 1 line.
Merge pull request #1305 from phil-davis/patch-2