Remove unused AsmPrinter OptLevel argument, and propogate.

- This more or less amounts to a revert of r65379. I'm curious to know what
   happened that caused this variable to become unused.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@74579 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Target/Mips/MipsTargetMachine.h

@@ -39,7 +39,6 @@ namespace llvm {
     // linked in.
     typedef FunctionPass *(*AsmPrinterCtorFn)(raw_ostream &o,
                                               MipsTargetMachine &tm,
-                                              CodeGenOpt::Level OptLevel,
                                               bool verbose);
     static AsmPrinterCtorFn AsmPrinterCtor;