LE_SCAN: Add runtime verbose logging for LE scan result parsing

* Also added default info log when throwing away extended advertisement
  in legacy scanning mode as this is a rare but worth noting event

Bug: 195318725
Test: BluetoothInstrumentationTests, flash and scan
Tag: #logging
Ignore-AOSP-First: Fix bug in an earlier release
Change-Id: I11ce228545226ec36465c70bdfced87d2e27f45e