Fix issue with accessibility when switching users

We need to unbind all services in unbindAllServicesLocked.
I was only unbinding all but one.

Fixes: 68814166
Test: Enabled Select to Speak, switched to guest, then
switched back. Previously S2S didn't restart. Now it does.

Change-Id: Ib6eb8ff7532a0c88faa3f14760dfd58774e3f5c2