Invalidate acl connection callbacks when destructed

The acl manager retains a pointer to the acl
connection callbacks after the connection is destructed.
Provide a mechanism to invalidate the callbacks to prevent use.

Bug: 213537005
Tag: #refactor
Test: gd/cert/run
BYPASS_LONG_LINES_REASON: Bluetooth likes 120 lines

Change-Id: Ia45af800c91ec456ae23673cf41ca4d41de20666