Revert "[WinEH] Add an EH registration and state insertion pass for 32-bit x86"

This reverts commit r236339, it breaks the win32 clang-cl self-host.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236340 91177308-0d34-0410-b5e6-96231b3b80d8

lib/CodeGen/AsmPrinter/AsmPrinter.cpp

@@ -266,8 +266,6 @@ bool AsmPrinter::doInitialization(Module &M) {
   case ExceptionHandling::WinEH:
     switch (MAI->getWinEHEncodingType()) {
     default: llvm_unreachable("unsupported unwinding information encoding");
-    case WinEH::EncodingType::Invalid:
-      break;
     case WinEH::EncodingType::Itanium:
       ES = new Win64Exception(this);
       break;