[x86] Add RetireControlUnit/RegisterFile descriptors to scheduling models.

[adibiagio]

Bugzilla Link	37854
Version	trunk
OS	Windows NT
Blocks	#31672
CC	@legrosbuffle,@topperc,@gchatelet,@LebedevRI,@RKSimon,@rotateright

Extended Description

At the moment, we only have RCU and the PRF entries for Btver2. We should add similar entries to other processor models too. For example, all the scheduling models related to Intel chips currently don't describe the reorder buffer and the register file.