trivial: remove unused Makefile
trivial: remove unused Makefile

Makefile is not used by anything infra related anymore, drop it.

Change-Id: I2c3e03cbf9a973a20262b22196e249d45ae6dbd0

openstack/akanda-appliance,stackforge/akanda-appliance,openstack/akanda-appliance,stackforge/akanda-appliance