Bluetooth: Stack certification

Modifications in stack for the stack 3.0 certification.

Change-Id: Ibbf3557c14c1ebf38eb743be578f3e7bd048e8c2
Bluetooth: GAP: Update Paging and inquiry busy level seperately

While updating the busy level of Paging or inquiry '10' was
used as BL for paging and inquiry,this leads to ignore the
one of them when both of them are active.

Made unique busy level for paging related events and inquiry
related events, so that each event will be notified.

CRs-Fixed: 580854,570163

Change-Id: I7bddcb4901061c450555235717b7d49bab922ae8
Bluetooth: GAP: Serialize the commands during Pairing process

Serialize the Remote version, Remote features, Authentication
requested commands.

This will make sure the above commands doesn't go simultaneously
to the remote device which can't handle the multiple comands
at a time.

CRs-Fixed: 592536
Change-Id: I4448c291a60ee637dc5927806547e67f26571d86
Fix compile without Bluetooth LE stack included

Commit 29f2e9c... ("Bluetooth: Implementation of LPP and extended LE
scan") breaks the compile on devices which don't include Bluetooth LE
support.  Fix the breakage by guarding new code which depends on the BLE
stack with #ifdefs.

Change-Id: I823673ffe64f08b060ec0db59f40c724b61ff345