Add phony targets for go binary modules

Add custom handling to androidmk.go for the bootstrap.GoBinaryTool
interface in order to create .PHONY targets for each tool written
in go.

Bug: 64539926
Test: m checkbuild
Test: m androidmk
Test: m multiproduct_kati
Change-Id: Ic65faa27a6ee4dfbd54ed6d208091db7c1d657a2