StaticAnalyzer/Core/ExprEngineCallAndReturn.cpp: Appease msvc.

0 (as nullptr) is incompatible to pointer in type matching on msvc.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@167355 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed