Remove vintf_service.

The only distinction that matters for security is if a service is
served by vendor or not AND which process is allowed to talk to which.

coredomain is allowed to talk to vintf_service OR vendor_service, it's
just that for a non-@VintfStability service user-defined APIs (as
opposed to pingBinder/dump) are restricted.

Bug: 136027762
Test: N/A
Change-Id: If3b047d65ed65e9ee7f9dc69a21b7e23813a7789
3 files changed