[clang-tidy] Suggest including <cmath> if necessary in type-promotion-in-math-fn-check.

Reviewers: alexfh

Subscribers: JDevlieghere, cfe-commits

Differential Revision: https://reviews.llvm.org/D27748

git-svn-id: https://llvm.org/svn/llvm-project/clang-tools-extra/trunk@289637 91177308-0d34-0410-b5e6-96231b3b80d8
3 files changed