Automatically reconnect sensors

Automatically reenable sensor connections for static sensors after a
Sensors HAL crash.

Bug: 111070257
Test: Request sensor events via a_sns_test, kill the sensors HAL,
      verify that events are no longer received, restart the HAL and
      verify that a_sns_test receives new sensor events.

Change-Id: I2baa7745cf07e29c186ac4b80679393d6e48bd56