ANDROID: vendor_hooks: add hook and OEM data for slab shrink

Some shrinker add lock in count_objects() may cause lock contention
issues and lead all task stall on slab shrink. Add vendor hook in
do_shrink_slab() for shrinker->count_objects() latency measuring.

Add 3 oem data in shrink_control struct. Two is for
shrinker->count_objects() and shrinker->scan_objects() latency
measuring, other one to store priority, some shrinker know the reclaimer
priority can control the memory reclaim more better.

Bug: 188684131

Change-Id: I80e9d90179bb52a99c54d9a067c6fcee835bb2ad
Signed-off-by: rongqianfeng <rongqianfeng@vivo.com>