[PowerPC] Rename some more VK_PPC_ enums

This renames more VK_PPC_ enums, to make them more closely reflect
the @modifier string they represent.  This also prepares for adding
a bunch of new VK_PPC_ enums in upcoming patches.

For consistency, some MO_ flags related to VK_PPC_ enums are
likewise renamed.

No change in behaviour.

llvm-svn: 184547
diff --git a/llvm/lib/Target/PowerPC/PPCISelDAGToDAG.cpp b/llvm/lib/Target/PowerPC/PPCISelDAGToDAG.cpp
index e006945..35f4b7c 100644
--- a/llvm/lib/Target/PowerPC/PPCISelDAGToDAG.cpp
+++ b/llvm/lib/Target/PowerPC/PPCISelDAGToDAG.cpp
@@ -1502,13 +1502,13 @@
         continue;
       break;
     case PPC::ADDIdtprelL:
-      Flags = PPCII::MO_DTPREL16_LO;
+      Flags = PPCII::MO_DTPREL_LO;
       break;
     case PPC::ADDItlsldL:
-      Flags = PPCII::MO_TLSLD16_LO;
+      Flags = PPCII::MO_TLSLD_LO;
       break;
     case PPC::ADDItocL:
-      Flags = PPCII::MO_TOC16_LO;
+      Flags = PPCII::MO_TOC_LO;
       break;
     }