rename getMDKind -> getMDKindID, make it autoinsert if an MD Kind
doesn't exist already, eliminate registerMDKind.  Tidy up a bunch
of random stuff.

llvm-svn: 92225
diff --git a/llvm/lib/AsmParser/LLParser.cpp b/llvm/lib/AsmParser/LLParser.cpp
index 48b6e87..a84336d 100644
--- a/llvm/lib/AsmParser/LLParser.cpp
+++ b/llvm/lib/AsmParser/LLParser.cpp
@@ -1123,11 +1123,8 @@
   if (ParseMDNode(Node)) return true;
 
   MetadataContext &TheMetadata = M->getContext().getMetadata();
-  unsigned MDK = TheMetadata.getMDKind(Name.c_str());
-  if (!MDK)
-    MDK = TheMetadata.registerMDKind(Name.c_str());
+  unsigned MDK = TheMetadata.getMDKindID(Name.c_str());
   MDsOnInst.push_back(std::make_pair(MDK, cast<MDNode>(Node)));
-
   return false;
 }