RFA: RX Sim: Use unsigned masks when setting flag bits

[Nick Clifton]

Hi DJ,

> I wonder if the definition of b2mask[] should have "UL" on the
> 0xfffffff too ?  It seems to work already though ;-)

I actually tested making the array contain long long masks, since they 
were being used to test against long long values, but this broke the 
computation that determines the carry bit, so I abandoned that change.

> Otherwise, I think this patch is OK.

Thanks - committed.

Cheers
   Nick

sim/ChangeLog

	* reg.c (set_oszc): Use unsigned int for the mask.
	(set_szc, set_osz, set_sz): Likewise.