Bluetooth: Retry pairing attempt again for pagetimeout

This is to add logic to retry pairing if it fails due to page timeout
or remote down. This allows to avoid lots of pairing failures if DUT
tries pairing when remote is trying to connect to previously connected
device.

Change-Id: Ic456406704846816c062923f8782b55e9fa1b96f
CRs-Fixed: 545387