Do not add quotes around flags argument

* build/soong will adds quotes around the whole flags
  and preserve the quotes around flags argument.
  The quotes incorrectly became part of a flag's value.
* build/soong adds automatically module directory to
  -header-filter.
* allow new found .h file clang-tidy warnings, not as errors.

Bug: 180862582
Test: make; make with WITH_TIDY=1
Change-Id: I460d56284a843ad5e85a36c47fc3981f49d04f4a