InputReader: Clear the multi-touch state when the device is reset

This is a partial revert of Change-Id:
Ic59d9fcb4e13fe262c422825c2485185004b719b

That CL introduced a behavior where the multi-touch state was never
reset, assuming there was no way to forcefully sync the state with the
kernel. This leads to issues when there are overflows of the kernel
buffer, in which case events may be dropped. Dropped events can lead to
the touch state being out of sync, which can result in behaviors such as
stuck pointers.

To avoid this, we will start resetting the touch state again when the
device is reset, such as after a buffer overflow.

We will follow this with the long-term fix of using EVIOCGMTSLOTS to
sync the multi-touch state in b/291626046.

Bug: 301332406
Test: atest inputflinger_tests
Test: manual, see b/301332406#comment24
Change-Id: If3027840bfff52adce086b853adc7284adf3777d