[clang-tidy] bugprone-not-null-terminated-result: checker adjustments 3

On Windows the signed/unsigned int conversions of APInt seems broken, so that
two of the test files marked as unsupported on Windows, as a hotfix.

git-svn-id: https://llvm.org/svn/llvm-project/clang-tools-extra/trunk@374713 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed