Move getService into libhidl.

This function is huge! By moving it out of auto-generated
code, we can do a couple of things:
- decrease the amount of space it takes (no longer not 'all'
  templated).
- make it easier to fix bugs like b/67425500

Bug: 67425500
Test: hidl_test, hidl_test_java

Change-Id: Ic8eb93d82e7bf8a6730d14109a36828bfe9d468a
3 files changed