Bluetooth: controller: Fix assert on different transaction collision

Updated the implementation of Connection Update Procedure to
not assert when peer master violates the Bluetooth
Specification v5.0 Vol.6 Part B Section 5.3 Procedure
Collisions. Instead disconnect the link with reason
Different Transaction Collision (0x2A).

Certain phones in the market perform Connection Update
Procedure and do not correctly handle remote initiated
colliding PHY update procedures. They try to perform both
the transactions involving an instant simultaneously
violating the Bluetooth Specifications.

Implementation in Zephyr is updated to gracefully handle
the violating remote master device, and not fatally assert
in the local device.

Relates to commit 8b3fd696 ("Bluetooth: controller: Fix
assert on different transaction collision")

Signed-off-by: Vinayak Kariappa Chettimada <vich@nordicsemi.no>