Revert "Re-commit r192758 - MC: quote tricky symbol names in asm output"

This caused the clang-native-mingw32-win7 buildbot to break.

The assembler was complaining about the following lines that were showing up
in the asm for CrashRecoveryContext.cpp:

  movl  $"__ZL16ExceptionHandlerP19_EXCEPTION_POINTERS@4", 4(%eax)
  calll "_AddVectoredExceptionHandler@8"
  .def   "__ZL16ExceptionHandlerP19_EXCEPTION_POINTERS@4";
  "__ZL16ExceptionHandlerP19_EXCEPTION_POINTERS@4":
  calll "_RemoveVectoredExceptionHandler@4"

Reverting for now.

llvm-svn: 192940
diff --git a/llvm/lib/MC/MCParser/COFFAsmParser.cpp b/llvm/lib/MC/MCParser/COFFAsmParser.cpp
index b3c0943..df1794c 100644
--- a/llvm/lib/MC/MCParser/COFFAsmParser.cpp
+++ b/llvm/lib/MC/MCParser/COFFAsmParser.cpp
@@ -295,7 +295,12 @@
 }
 
 bool COFFAsmParser::ParseSectionName(StringRef &SectionName) {
-  return getParser().parseIdentifier(SectionName);
+  if (!getLexer().is(AsmToken::Identifier))
+    return true;
+
+  SectionName = getTok().getIdentifier();
+  Lex();
+  return false;
 }
 
 // .section name [, "flags"]