audio policy: Remove unnecessary check for HMDI device switch

- Remove unnecessary check in setOutputDevice for HDMI device
Routing.
- This is a revert of Change-Id: If4f1845db0378b643392bec591cbd95fbe114634
- The original issue is fixed by Google bug id: 18144611

CRs-Fixed: 781821
Change-Id: Id38260217a3b45716d953a78d9a0950b9c94f195