sepolicy(hostapd): Add a HIDL interface for hostapd

Change sepolicy permissions to now classify hostapd as a HAL exposing
HIDL interface.

Sepolicy denial for accessing /data/vendor/misc/wifi/hostapd:
12-27 23:40:55.913  4952  4952 W hostapd : type=1400 audit(0.0:19): avc:
denied { write } for name="hostapd" dev="sda13" ino=4587601
scontext=u:r:hal_wifi_hostapd_default:s0
tcontext=u:object_r:system_data_file:s0 tclass=dir permissive=0

01-02 19:07:16.938  5791  5791 W hostapd : type=1400 audit(0.0:31): avc:
denied { search } for name="net" dev="sysfs" ino=30521
scontext=u:r:hal_wifi_hostapd_default:s0
tcontext=u:object_r:sysfs_net:s0 tclass=dir permissive=0

Bug: 36646171
Test: Device boots up and able to turn on SoftAp.
Change-Id: Ibacfcc938deab40096b54b8d0e608d53ca91b947