device: Save remote name request attempts into cache file

device: Save remote name request attempts into cache file

Since a peer device is potentially removed if not discovered for more
than 30 seconds, we would lost the remote name request activity when
the device is rediscovered. This could end up with a remote name
request much sooner than we intend it to be.

Therefore, put the RNR record into a cache file, so we can recover it
when the peer device is rediscovered.

Reviewed-by: Miao-chen Chou <mcchou@chromium.org>
Signed-off-by: Anuj Jain <anuj01.jain@samsung.com>
Signed-off-by: Ayush Garg <ayush.garg@samsung.com>