base: genlock: Remove genlock_release_lock and associated ioctl

Allowing a lock to be asynchronously released while a handle
was still active turned out to be too dangerous to use in a
multi-threaded environment and it served no pratical
purpose anyway.  Handles now hold an attached lock until they
are destroyed.

(cherry picked from commit 4df70a254d9ddea0ee4bede39d4d12e6360e5b99)

Change-Id: I969ac3cf84c5982cc7c03c5651c7fe328567c02b
CRs-fixed: 333141
Signed-off-by: Jordan Crouse <jcrouse@codeaurora.org>