libbinder_ndk: convenience method for okay status

Before:
 return ScopedAStatus(AStatus_newOk());

After:
 return ScopedAStatus::ok();

Bug: 111445392
Test: atest android.binder.cts (using this)
Change-Id: Id45528c101ff3a965d7c84ff5946e48179bf9285
1 file changed