Remove CallingConvMethodType

This seems to be an old vestage of a previous implementation of getting
the default calling convention, and everything is now using
CXXABI/ASTContext's getDefaultCallingConvention.  Remove it, since it
isn't doing anything.

llvm-svn: 367039
diff --git a/clang/lib/Basic/Targets/SPIR.h b/clang/lib/Basic/Targets/SPIR.h
index 6023c86..802ccf8 100644
--- a/clang/lib/Basic/Targets/SPIR.h
+++ b/clang/lib/Basic/Targets/SPIR.h
@@ -88,7 +88,7 @@
                                                             : CCCR_Warning;
   }
 
-  CallingConv getDefaultCallingConv(CallingConvMethodType MT) const override {
+  CallingConv getDefaultCallingConv() const override {
     return CC_SpirFunction;
   }