[llvm-lib] Pass the right value of MingwDef to parseCOFFModuleDefinition

[mstorsjo]

Summary

In llvm-lib cases, the MinGW specific behaviours shouldn't be
enabled.

Not adding any tests to check the corner case behaviours, as this
simply was a mistake when this codepath was added in
395ec4458fb7fc700551f7017c0a395d68c55873 / D144765.

[hans]

lgtm

llvm/lib/ToolDrivers/llvm-lib/LibDriver.cpp

if (!MB)
       return 1;
 
     if (!MB->getBufferSize()) {
       llvm::errs() << "definition file empty\n";
       return 1;
     }
 
     Expected<COFFModuleDefinition> Def =
-        parseCOFFModuleDefinition(*MB, LibMachine, true);
+        parseCOFFModuleDefinition(*MB, LibMachine, /*MingwDef=*/false);
 
     if (!Def) {
       llvm::errs() << "error parsing definition\n"
                    << errorToErrorCode(Def.takeError()).message();
       return 1;
     }
 
     return writeImportLibrary(Def->OutputFile, OutputPath, Def->Exports,