Assert fail on SIMD vector types

[john-h-kastner]

An assertion fails when processing expressions with vector types such as those in this header file.

#include <tmmintrin.h>

cconv-standalone: /home/cc/checkedc-clang/clang/lib/CConv/ConstraintResolver.cpp:570: CVarSet ConstraintResolver::getExprConstraintVars(clang::Expr*): Assertion `"InitlistExpr of type other than array or pointer in " "getExprConstraintVars" && ILE->getType()->isPointerType()' failed.

Reduced test case obtained from the header:

__attribute__((__vector_size__(2 * sizeof(long)))) int a() {
  return (__attribute__((__vector_size__(2 * sizeof(long))))int){};
}

[john-h-kastner]

This was resolved by #633