Introduce fromBinder() helper.

To safely cast binder objects back to HIDL interfaces.

Modified toBinder(), to take into account IHw
classes no longer exist.

Removed an obsolete conversion of IFoo to BnFoo
in the servicemanager add macro - BnFoo is transport
specific and does not belong there.

Test: mma, hidl_test, hidl_test_java
Bug: 33173166
Change-Id: Iae84c900584a008c9cc8e03d1914e95d0fae77ce
4 files changed