Change the Opcode enum for PHI nodes from "Instruction::PHINode" to "Instruction::PHI" to be more consistent with the other instructions.

llvm-svn: 9269
diff --git a/llvm/lib/VMCore/Instruction.cpp b/llvm/lib/VMCore/Instruction.cpp
index 179a988..b6bedf4 100644
--- a/llvm/lib/VMCore/Instruction.cpp
+++ b/llvm/lib/VMCore/Instruction.cpp
@@ -87,7 +87,7 @@
   case GetElementPtr: return "getelementptr";
     
   // Other instructions...
-  case PHINode: return "phi";
+  case PHI:     return "phi";
   case Cast:    return "cast";
   case Call:    return "call";
   case Shl:     return "shl";