find7a: add default/automatic brightness overlays

- enable autobrightness by default
- make default brightness 82 / 32%
- make default screen timeout 30 seconds

from hammerhead overlays

Change-Id: I4a7829d8ee54d36d4f5208e01cd9bce0d5c9367b
Misc

Change-Id: I5e581096d24a94b4498ed0611f5840a518bc7031
Signed-off-by: ayysir <dresadd09691@gmail.com>