Remove dormant BrickReceiver

This gem of a class doesn't appear to be wired up in any functional way,
so give it a well-deserved retirement into git history.

Note: This was discovered when refining keep rules in system_server
to more accurate reflect services kept by the framework manifest.

Test: m
Bug: 272495195
Change-Id: I9279ee19b3b20871b190aceae586e0828f3b2bd5