scripts/Makefile.docker: allow calling from a different directory

diff --git a/scripts/Makefile.docker b/scripts/Makefile.docker
index f32386e60be3a861f461a75f9eeba247b7e3b09f..71908e058c518e1ab258b6ad777e2a9f1dbac3d1 100644 (file)
--- a/scripts/Makefile.docker
+++ b/scripts/Makefile.docker
@@ -12,10 +12,13 @@ RELTAG              = $(shell [ -n "${RELEASE}" ] && echo "-t ${BASETAG}:${RELEASE}" || echo
 BUILDXDETECT   = ${HOME}/.docker/cli-plugins/docker-buildx
 QEMUDETECT     = /proc/sys/fs/binfmt_misc/qemu-m68k
 
+# https://stackoverflow.com/a/324782
+ROOT_DIR:=$(dir $(realpath $(lastword $(MAKEFILE_LIST))))/..
+
 docker-multiarch: qemu buildx docker-multiarch-builder
        docker login
        docker buildx build --no-cache --builder docker-multiarch --pull --push \
-                           --platform ${PLATFORMS} ${RELTAG} ..
+                           --platform ${PLATFORMS} ${RELTAG} ${ROOT_DIR}
 
 qemu: ${QEMUDETECT}
 ${QEMUDETECT}: