Don't use hack/make.sh for validate-vet

hack/make.sh now does not make a difference, so simplify.

Signed-off-by: Miloslav Trmač <mitr@redhat.com>

hack/validate-vet.sh

@@ -0,0 +1,16 @@
+#!/bin/bash
+
+errors=$(go vet -tags="${BUILDTAGS}" $(go list -e ./...))
+
+if [ -z "$errors" ]; then
+	echo 'Congratulations!  All Go source files have been vetted.'
+else
+	{
+		echo "Errors from go vet:"
+		echo "$errors"
+		echo
+		echo 'Please fix the above errors. You can test via "go vet" and commit the result.'
+		echo
+	} >&2
+	exit 1
+fi