Add sepolicy rules to grant wificond permission to use SIOCSIFHWADDR
ioctl. This permission is needed to dynamically change MAC address of
the device when connecting to wifi networks.

Bug: 63905794
Test: Verified manually that wificond can dynamically change MAC
address.

Change-Id: If2c6b955b0b792f706d8438e8e2e018c0b4cfc31