P2P: Consider age for the P2P scan results

P2P: Consider age for the P2P scan results

cfg80211 caches the scan results according the channel number. Due to
the 15 sec aging this might cause the user mode to see more than one
scan result with the same BSSID, e.g. - one scan result for the
P2P Device and one for the P2P GO (once it's enabled).

Fix this by updating the device entry only if the new peer entry is
newer than the one previously stored.

Signed-off-by: Yoni Divinsky <yoni.divinsky@ti.com>
Signed-off-by: Victor Goldenshtein <victorg@ti.com>
Signed-off-by: Igal Chernobelsky <igalc@ti.com>
Signed-hostap: Arik Nemtsov <arik@wizery.com>