Switch from HIDL DisplayCapability to AIDL

In preparation for adding a new DisplayCapability which is only in AIDL.
This change is almost completely mechanical, and should have no impact
on behavior.

Similar to I1f923fcc8d8e6dff388493a76e31d435638b5255 for Composition.

Bug: 193170859
Test: existing tests
Change-Id: I448d5d0ec71f99fb3cbfbe505ded40ab37f6083b