Retire hwc2/MiniFence

sp<MiniFence> is replaced by shared_ptr<unique_fd>.

Bug: 154346346
Test: boot
Signed-off-by: Roman Kiryanov <rkir@google.com>
Merged-In: Id02e959b897e6e667e092705815d1082da15a2b4
Change-Id: Ic2ba6df78bdc3138e0c617feece75fccb250200f
4 files changed