Auto Pairing tweaks.

When the stack returns an incorrect error code, we were going on
in a loop trying auto pairing. Ideally, the stack shouldn't be returning
this incorrect code, but add a fail safe in the userspace code.

Also cap attempts at 2. There is no point trying more than that.

Change-Id: I5bf3ea871b9c2241ae5ac88e9818c9eb847fac92