add a BUILD_IMAGE variable to the Makefile

This change helps make it easier substitute different build images when
using the makefile. The user can now specify an alternate container
image to use for building the mao binaries, for example
`BUILD_IMAGE=quay.io/foo/mybuilder make build`.

Makefile

@@ -33,6 +33,7 @@ REPO_PATH   ?= sigs.k8s.io/cluster-api-provider-aws
 LD_FLAGS    ?= -X $(REPO_PATH)/pkg/version.Raw=$(VERSION) -extldflags "-static"
 MUTABLE_TAG ?= latest
 IMAGE        = origin-aws-machine-controllers
+BUILD_IMAGE ?= openshift/origin-release:golang-1.16
 
 # race tests need CGO_ENABLED, everything else should have it disabled
 CGO_ENABLED = 0
@@ -60,7 +61,7 @@ ifeq ($(NO_DOCKER), 1)
   DOCKER_CMD =
   IMAGE_BUILD_CMD = imagebuilder
 else
-  DOCKER_CMD = $(ENGINE) run --rm -e CGO_ENABLED=$(CGO_ENABLED) -e GOARCH=$(GOARCH) -e GOOS=$(GOOS) -v "$(PWD)":/go/src/sigs.k8s.io/cluster-api-provider-aws:Z -w /go/src/sigs.k8s.io/cluster-api-provider-aws openshift/origin-release:golang-1.16
+  DOCKER_CMD = $(ENGINE) run --rm -e CGO_ENABLED=$(CGO_ENABLED) -e GOARCH=$(GOARCH) -e GOOS=$(GOOS) -v "$(PWD)":/go/src/sigs.k8s.io/cluster-api-provider-aws:Z -w /go/src/sigs.k8s.io/cluster-api-provider-aws $(BUILD_IMAGE)
   IMAGE_BUILD_CMD = $(ENGINE) build
 endif
 

go.mod

@@ -1,6 +1,6 @@
 module sigs.k8s.io/cluster-api-provider-aws
 
-go 1.16
+go 1.17
 
 require (
 	github.com/aws/aws-sdk-go v1.38.23