miniupnpd: Enable regex filter

miniupnpd: Enable regex filter

UPnP rules now may have an optional regex filter on requester's
descriptions. This is a countermeasure against some UPnP exploiters
without shutting down UPnP service completely, albeit they can bypass it
by reporting innocent's descriptions maliciously.

Since the filter specifier is optional, existing valid config files will
still work.

This increases the executable's size by 1.3 kB from original 147.7 kB on
i386.

Signed-off-by: David Yang <mmyangfl@gmail.com>