Revert "Bluetooth: hci_conn: Consolidate code for aborting connections"

This reverts commit 6083089a which is
commit a13f316e upstream.

It breaks the Android kernel abi and can be brought back in the future
in an abi-safe way if it is really needed.

Bug: 161946584
Change-Id: Ic482b9be644466e06baa4bc0f01a7cbf63b905fb
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>