o Fix ipfw uid rules: socheckuid() returns 0 when uid matches a socket cr_uid.
o Fix ipfw uid rules: socheckuid() returns 0 when uid matches a socket
cr_uid.

Note: we do not have socheckuid() in RELENG_4, ip_fw2.c uses its
own macro for a similar purpose that is why ipfw2 in RELENG_4 processes
uid rules correctly. I will MFC the diff for code consistency.

Reported by:	Oleg Baranov <ol@csa.ru>
Reviewed by:	luigi
MFC after:	1 month

jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase