netif/dc Updates

[Matthew Dillon]

:Taken-from: FreeBSD
:           if_dc.c       1.9.46,48,49,50,51,52,53,55
:           if_dcreg.h   1.4.2.23,24,25
:
:
:<http://pornadmin.net/~tongson/bsd/dc-20050715.diff>
:
:--ed
:Eduardo Tongson

    Committed!

					-Matt
					Matthew Dillon 
					<dillon at xxxxxxxxxxxxx>