Use the last updated MAC address before turning on wifi

Use the last updated MAC address before turning on wifi

MAC randomization does not work properly when there are multiple wifi interfaces
or in some devices that do not create a .mac.info file.
So, to solve this problem, a permanent MAC address that is set before wifi up is used.

If a permanent MAC address is in built-in physical device,
it's hardly get it at an initial creation.
So, if there is a MAC address updated from netlink before wifi is on, it is used.
* MAC randomization works only when wifi is turned on.

Change-Id: Ia7a9ad0affaa6deca974199100a56e7378b6c195
Signed-off-by: Jaehyun Kim <jeik01.kim@samsung.com>