dynamic_sensor: Add sensor manager init to sub-HAL 2.1.

Bug: 195964858
Test: Verified dynamic sensor manager is present in sensor list and that
 no SELinux violations occur.
Test: See details in testing done comment in
 https://googleplex-android-review.git.corp.google.com/15874906 .
Change-Id: I5d587dc46bdec66c3162bf222d36b285b8d2ca3d
3 files changed