Correcting values in NX and MMU initfiles

> Implementing bits definition in nx initfile
> Modifying fir values in mmu initfile to compensate for deadbits

Change-Id: Ic80450da6196e2e5a9eab424ab6af4898ec58278
Original-Change-Id: I79e7ffb367db2a3505a25d3e0455c5f875e5304a
Reviewed-on: http://ralgit01.raleigh.ibm.com/gerrit1/28451
Tested-by: Jenkins Server <pfd-jenkins+hostboot@us.ibm.com>
Tested-by: Hostboot CI <hostboot-ci+hostboot@us.ibm.com>
Reviewed-by: Prachi Gupta <pragupta@us.ibm.com>
Reviewed-by: Joseph J. McGill <jmcgill@us.ibm.com>
Reviewed-by: Jennifer A. Stofer <stofer@us.ibm.com>
Reviewed-on: http://ralgit01.raleigh.ibm.com/gerrit1/36651
Reviewed-by: Daniel M. Crowell <dcrowell@us.ibm.com>
Tested-by: Daniel M. Crowell <dcrowell@us.ibm.com>