1. Fixed a bug in the condition to check if cental know LE link key.

The intention of the code is to check if it has a LE link key, but only other bits are checked at now.

2. Changed the order of condition to check key missing on peripheral
in order to process key missing case, it must have a higher priority than checking LE link key.

Bug: 300190678
Test:
After pairing both devices, delete the pairing only from the peripheral side.
Then connect the two devices to BLE.

Change-Id: Ib2ee29b6b5dd6a54b3a7f481579d078c5cecb493