misc/cgo/test: remove unused Makefile
misc/cgo/test: remove unused Makefile

R=golang-dev, minux.ma, iant
CC=golang-dev
http://codereview.appspot.com/6459091
abustany/go,abustany/go,abustany/go,abustany/go,abustany/go,abustany/go,abustany/go