Add workaround for Yukon FE+ A0. This controller is known to have

Add workaround for Yukon FE+ A0. This controller is known to have
severe silicon bugs that can't handle VLAN hardware tagging as well
as status LE writeback bug. The status LE writeback bug is so
critical we can't trust status word of received frame. To accept
frames on Yukon FE+ A0 msk(4) just do minimal check for received
frames and pass them to upper stack. This means msk(4) can pass
corrupted frames to upper layer. You have been warned!
Also I supposed RX_GMF_FL_THR to be 32bits register but Linux
driver treated it as 16bit register so follow their leads. At least
this does not seem to break msk(4) on Yukon FE+.

Tested by:	bz, Tanguy Bouzeloc ( the.zauron <> gmail dot com )
		Bruce Cran ( bruce <> cran dot org dot uk )
		Michael Reifenberger ( mike <> reifenberger dot com )
		Stephen Montgomery-Smith ( stephen <> missouri dot edu )