[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/PPCCodeEmitter.cpp b/llvm/lib/Target/PowerPC/PPCCodeEmitter.cpp
index 40e4968..0ad4ea3 100644
--- a/llvm/lib/Target/PowerPC/PPCCodeEmitter.cpp
+++ b/llvm/lib/Target/PowerPC/PPCCodeEmitter.cpp
@@ -201,8 +201,8 @@
   unsigned RelocID;
   switch (MO.getTargetFlags() & PPCII::MO_ACCESS_MASK) {
     default: llvm_unreachable("Unsupported target operand flags!");
-    case PPCII::MO_HA16: RelocID = PPC::reloc_absolute_high; break;
-    case PPCII::MO_LO16: RelocID = PPC::reloc_absolute_low; break;
+    case PPCII::MO_LO: RelocID = PPC::reloc_absolute_low; break;
+    case PPCII::MO_HA: RelocID = PPC::reloc_absolute_high; break;
   }
 
   MCE.addRelocation(GetRelocation(MO, RelocID));