Revert "add the -mrecip driver flag and process its options (2nd try)"

This reverts commit r238851.

It depends on a llvm commit that was reverted.

llvm-svn: 238904

clang/lib/Frontend/CompilerInvocation.cpp

@@ -1846,7 +1846,7 @@ static void ParseTargetArgs(TargetOptions &Opts, ArgList &Args) {
   Opts.FeaturesAsWritten = Args.getAllArgValues(OPT_target_feature);
   Opts.LinkerVersion = Args.getLastArgValue(OPT_target_linker_version);
   Opts.Triple = llvm::Triple::normalize(Args.getLastArgValue(OPT_triple));
-  Opts.Reciprocals = Args.getAllArgValues(OPT_mrecip_EQ);
+
   // Use the default target triple if unspecified.
   if (Opts.Triple.empty())
     Opts.Triple = llvm::sys::getDefaultTargetTriple();