Treblelize bug_map: auditd read bug_map from multiple partitions

Goal is to allow product-specific bug_map definitions be read from
/system or /system_ext, so that during cross-version GRF testing the
bug_map definitions are loaded from vendor (version N) and
/system & /system_ext (version N+1).
Replace <fstream> & <sstream> with libbase idioms.

Bug: 177977370
Test: Boot and check auditd logs
Change-Id: I4ba84d1f415b71e3934a9688eeff1a6b616added
1 file changed
tree: 2a42bb8e5dc8cc857708eb5c0eaf1d16fb9e32a5
  1. liblog/
  2. logcat/
  3. logd/
  4. logwrapper/
  5. rust/
  6. OWNERS
  7. PREUPLOAD.cfg
  8. TEST_MAPPING