Remove now unused isoPath link parameter

It was removed from version in 9adf5438

And removed from the ISO URL in 39670fc0

Makefile

@@ -108,7 +108,7 @@ STORAGE_PROVISIONER_MANIFEST ?= $(REGISTRY)/storage-provisioner:$(STORAGE_PROVIS
 STORAGE_PROVISIONER_IMAGE ?= $(REGISTRY)/storage-provisioner-$(GOARCH):$(STORAGE_PROVISIONER_TAG)
 
 # Set the version information for the Kubernetes servers
-MINIKUBE_LDFLAGS := -X k8s.io/minikube/pkg/version.version=$(VERSION) -X k8s.io/minikube/pkg/version.isoVersion=$(ISO_VERSION) -X k8s.io/minikube/pkg/version.isoPath=$(ISO_BUCKET) -X k8s.io/minikube/pkg/version.gitCommitID=$(COMMIT) -X k8s.io/minikube/pkg/version.storageProvisionerVersion=$(STORAGE_PROVISIONER_TAG)
+MINIKUBE_LDFLAGS := -X k8s.io/minikube/pkg/version.version=$(VERSION) -X k8s.io/minikube/pkg/version.isoVersion=$(ISO_VERSION) -X k8s.io/minikube/pkg/version.gitCommitID=$(COMMIT) -X k8s.io/minikube/pkg/version.storageProvisionerVersion=$(STORAGE_PROVISIONER_TAG)
 PROVISIONER_LDFLAGS := "-X k8s.io/minikube/pkg/storage.version=$(STORAGE_PROVISIONER_TAG) -s -w -extldflags '-static'"
 
 MINIKUBEFILES := ./cmd/minikube/