Fix the polly build.
Rename PPCSubTarget to Subtarget in PPCTargetLowering for consistency.
Also remove an extra local subtarget in the initialization functions.
Remove an extraneous this-> to access the subtarget.
Check the access of operator delete from the destructor context

Previously we would do the access check from the context of
MarkVTableUsed.

Also update this test to C++11, since that is typically used with the MS
C++ ABI.

Fixes PR20005.