Delete TouchState::deviceId

We are doing per-device pointer tracking now, so this CL helps remove
the assumptions around having a single active device.

For now, the behaviour is preserved. In the future, we will not need to
check the currently active device at the TouchState level.

Bug: 211379801
Test: m inputflinger_tests && $ANDROID_HOST_OUT/nativetest64/inputflinger_tests/inputflinger_tests
Change-Id: Ie13e9c93eefc04c2955de3b8a06c9c2da28c9d72