Add a new ANALYZER severity group.

* Separate clang-tidy's clang-analyzer-* warnings from
  other clang-tidy warnings.

Bug: 31559947
Test: build with WITH_TIDY=1 and DEFAULT_GLOBAL_TIDY_CHECKS=*,-readability-*,-google-readability-*
Change-Id: If03c421c9319741ef6588bc0d803b6da0cc4433a
1 file changed