Change accesses to IS_SIM to use mss accessor

Change-Id: Ice151f9f732c04160247ac153b656cdf8629f5d7
Original-Change-Id: Iafcaddbca510c29fb4a0289490b90b539dde2b13
Reviewed-on: http://ralgit01.raleigh.ibm.com/gerrit1/37610
Reviewed-by: Brian R. Silver <bsilver@us.ibm.com>
Tested-by: Jenkins Server <pfd-jenkins+hostboot@us.ibm.com>
Tested-by: Hostboot CI <hostboot-ci+hostboot@us.ibm.com>
Reviewed-by: STEPHEN GLANCY <sglancy@us.ibm.com>
Reviewed-by: Jennifer A. Stofer <stofer@us.ibm.com>
Reviewed-on: http://ralgit01.raleigh.ibm.com/gerrit1/38762
Tested-by: Jenkins OP Build CI <op-jenkins+hostboot@us.ibm.com>
Tested-by: FSP CI Jenkins <fsp-CI-jenkins+hostboot@us.ibm.com>
Reviewed-by: Daniel M. Crowell <dcrowell@us.ibm.com>

Author: JacobHarvey

src/import/chips/p9/procedures/hwp/memory/lib/phy/read_cntrl.H

@@ -364,7 +364,7 @@ inline fapi2::ReturnCode reset_config2( const fapi2::Target<T>& i_target )
     fapi2::buffer<uint64_t> l_data;
 
     // Bogus Centaur SIM number from init file - use 8 per Bialas 2/16
-    // ---48:52, 0b00000, (def_is_sim); # CONSEQ_PASS  sim value---
+    // ---48:52, 0b00000, (def_l_sim); # CONSEQ_PASS  sim value---
     // 48:52, 0b01000, (def_is_bl8); # CONSEQ_PASS  8 from SWyatt
     // 48:52, 0b01111, any;          # CONSEQ_PASS  16 min for BL4, or OTF