Add tidy-soong, tidy-dir-path, module-tidy targets

* When WITH_TIDY=1, these targets allow quick check of C/C++
  source code with clang-tidy, without building C/C++ binaries.
* For each module with tidy rules, add a module-tidy target, e.g.,
  libart-tidy, libartd-tidy, bionic-benchmarks-tidy, libnativehelper-tidy, etc.
* Add a tidy-soong phony target that depends on all module-tidy targets.
* For each directory X/Y add a tidy-X-Y phony target that depends
  on all *-tidy targets in X/Y and tidy-X-Y-Z for all X/Y/Z directories,
  e.g., tidy-bionic, tidy-bionic-benchmarks, tidy-libnativehelper, etc.
* Only soong modules are collected for now.
  Tidy rules in .mk files will be collected later.
* Some comment lines reformatted by gofmt.

Test: WITH_TIDY=1 make <some_module>-tidy tidy-<some_directory>
Test: WITH_TIDY=1 make tidy-soong
Bug: 199169329
Change-Id: I45aef3875f70288a8e070761e5f083dbbdfa6e94