Revert r183854 (PPC: Fix switch warnings from r183841)

Now that the PRED_BAD has been removed, this is failing the Clang
-Werror build due to -Wcovered-switch-default.

llvm-svn: 183863
diff --git a/llvm/lib/Target/PowerPC/MCTargetDesc/PPCPredicates.cpp b/llvm/lib/Target/PowerPC/MCTargetDesc/PPCPredicates.cpp
index 1c69a0b..853e505 100644
--- a/llvm/lib/Target/PowerPC/MCTargetDesc/PPCPredicates.cpp
+++ b/llvm/lib/Target/PowerPC/MCTargetDesc/PPCPredicates.cpp
@@ -18,7 +18,6 @@
 
 PPC::Predicate PPC::InvertPredicate(PPC::Predicate Opcode) {
   switch (Opcode) {
-  default: llvm_unreachable("Unknown PPC branch opcode!");
   case PPC::PRED_EQ: return PPC::PRED_NE;
   case PPC::PRED_NE: return PPC::PRED_EQ;
   case PPC::PRED_LT: return PPC::PRED_GE;
@@ -28,11 +27,11 @@
   case PPC::PRED_NU: return PPC::PRED_UN;
   case PPC::PRED_UN: return PPC::PRED_NU;
   }
+  llvm_unreachable("Unknown PPC branch opcode!");
 }
 
 PPC::Predicate PPC::getSwappedPredicate(PPC::Predicate Opcode) {
   switch (Opcode) {
-  default: llvm_unreachable("Unknown PPC branch opcode!");
   case PPC::PRED_EQ: return PPC::PRED_EQ;
   case PPC::PRED_NE: return PPC::PRED_NE;
   case PPC::PRED_LT: return PPC::PRED_GT;
@@ -42,5 +41,6 @@
   case PPC::PRED_NU: return PPC::PRED_NU;
   case PPC::PRED_UN: return PPC::PRED_UN;
   }
+  llvm_unreachable("Unknown PPC branch opcode!");
 }