Makefile cleanup (#903)

Remove unused distclean and misc.
Signed-off-by: Yong Tang <yong.tang.github@outlook.com>

Makefile

-GITCOMMIT     := $(shell git describe --dirty --always)
-
-BUILD_VERBOSE := -v
-
-TEST_VERBOSE := -v
+GITCOMMIT:=$(shell git describe --dirty --always)
 
 all: coredns
 
@@ -10,22 +6,18 @@ all: coredns
 # TODO: Add .go file dependencies.
 .PHONY: coredns
 coredns: check godeps
-	CGO_ENABLED=0 go build $(BUILD_VERBOSE) -ldflags="-s -w -X github.com/coredns/coredns/coremain.gitCommit=$(GITCOMMIT)"
-
-.PHONY: deps
-deps: core/zmiddleware.go core/dnsserver/zdirectives.go godeps
-	go get -u github.com/golang/lint/golint
+	CGO_ENABLED=0 go build -v -ldflags="-s -w -X github.com/coredns/coredns/coremain.gitCommit=$(GITCOMMIT)"
 
 .PHONY: check
-check: fmt deps
+check: fmt core/zmiddleware.go core/dnsserver/zdirectives.go godeps
 
 .PHONY: test
 test: check
-	go test -race $(TEST_VERBOSE) ./test ./middleware/...
+	go test -race -v ./test ./middleware/...
 
 .PHONY: testk8s
 testk8s: check
-	go test -race $(TEST_VERBOSE) -tags=k8s -run 'TestKubernetes' ./test ./middleware/kubernetes/...
+	go test -race -v -tags=k8s -run 'TestKubernetes' ./test ./middleware/kubernetes/...
 
 .PHONY: godeps
 godeps:
@@ -39,18 +31,13 @@ coverage: check
 	set -e -x
 	echo "" > coverage.txt
 	for d in `go list ./... | grep -v vendor`; do \
-		go test $(TEST_VERBOSE)  -tags 'etcd k8s' -race -coverprofile=cover.out -covermode=atomic -bench=. $$d || exit 1; \
+		go test -v  -tags 'etcd k8s' -race -coverprofile=cover.out -covermode=atomic -bench=. $$d || exit 1; \
 		if [ -f cover.out ]; then \
 			cat cover.out >> coverage.txt; \
 			rm cover.out; \
 		fi; \
 	done
 
-.PHONY: clean
-clean:
-	go clean
-	rm -f coredns
-
 core/zmiddleware.go core/dnsserver/zdirectives.go: middleware.cfg
 	go generate coredns.go
 
@@ -65,17 +52,13 @@ fmt:
 		(echo "please format Go code with 'gofmt -s -w'" && false)
 
 .PHONY: lint
-lint: deps
+lint:
 	## run go lint, suggestion only (not enforced)
+	go get -u github.com/golang/lint/golint
 	@test -z "$$(find . -type d | grep -vE '(/vendor|^\.$$|/.git|/.travis)' | grep -vE '(^\./pb)' | xargs golint \
 		| grep -vE "context\.Context should be the first parameter of a function" | tee /dev/stderr)"
 
-.PHONY: distclean
-distclean: clean
-	# Clean all dependencies and build artifacts
-	find $(GOPATH)/pkg -maxdepth 1 -mindepth 1 | xargs rm -rf
-	find $(GOPATH)/bin -maxdepth 1 -mindepth 1 | xargs rm -rf
-
-	find $(GOPATH)/src -maxdepth 1 -mindepth 1 | grep -v github | xargs rm -rf
-	find $(GOPATH)/src -maxdepth 2 -mindepth 2 | grep -v miekg | xargs rm -rf
-	find $(GOPATH)/src/github.com/miekg -maxdepth 1 -mindepth 1 \! -name \*coredns\* | xargs rm -rf
+.PHONY: clean
+clean:
+	go clean
+	rm -f coredns