Resolve Pairing failure with IPhone

Resolve Pairing failure with IPhone

When pairing is initiated from the iPhone side, it sets Bonding bit
without MITM. We responded to this with No bonding, No MITM. This resulted
in JustWorks & Unauthenticated link key. After pairing iPhone initiates a
RFCOMM connection. This caused a link key upgrade to be done, which the iPhone
rejected, resulting in pairing failure. To resolve this the following
enhancements were made
1. If locally initiated pairing always set Bonding bit + MITM
2. If remote initiated
a. copy over the bonding bit
b. if peer has DisplayYesNo set MITM
3. As a fallback if remote had MITM, enable MITM in our response
This forces pairing to use Bonding bit+MITM thus resulting in authenticated
combination linkkey

Change-Id: I08f16c80821bc822023180d01868614ba41e6d88