Add PersistableBundle.aidl into binder includes

Add the PersistableBundle.aidl into the new /aidl/binder/
subdirectory (along with the necessary 'android' and 'os'
subdirectories) so that the aidl file will live alongside
its native implementation in libbinder. This change will
allow native-only Android checkouts (e.g. Brillo) to use
PersistableBundle.

The /aidl/ subdirectory should henceforth contain any
aidl files that live with native code.

BUG: 26292234
Change-Id: I07b49dad8afd679f33e41fa9044dffc02ec25e3e