canCastInterface: always return true for IBase

Don't do a binder call for passing interface
around, especially since every HIDL thing is
already IBase.

Bug: 68217907
Test: hidl's run_all_device_tests, boot + camera/YT sanity
Merged-In: Ic195e9c19f181828296c515a3004c75daccdd03f
Change-Id: Ic195e9c19f181828296c515a3004c75daccdd03f
(cherry picked from commit b2bf30d7009674938a96ff9ae87a30e9ab260dc6)