[openwrt/openwrt] layerscape: make boot filesystem reproducible

[LEDE Commits]

dangole pushed a commit to openwrt/openwrt.git, branch master:
https://git.openwrt.org/1c7e146f7e0f42e5e414c6cff0c73f75b405e0dd

commit 1c7e146f7e0f42e5e414c6cff0c73f75b405e0dd
Author: Daniel Golle <daniel at makrotopia.org>
AuthorDate: Mon Mar 28 18:26:13 2022 +0100

    layerscape: make boot filesystem reproducible
    
    Set timestamp option for make_ext4fs to make boot filesystem
    reproducible.
    
    Signed-off-by: Daniel Golle <daniel at makrotopia.org>
---
 target/linux/layerscape/image/Makefile | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/target/linux/layerscape/image/Makefile b/target/linux/layerscape/image/Makefile
index 3c8bdea480..52dc532c34 100644
--- a/target/linux/layerscape/image/Makefile
+++ b/target/linux/layerscape/image/Makefile
@@ -36,7 +36,9 @@ endef
 define Build/ls-append-kernel
 	mkdir -p $@.tmp && \
 	cp $(IMAGE_KERNEL) $@.tmp/fitImage && \
-	make_ext4fs -J -L kernel -l "$(LS_SD_KERNELPART_SIZE)M" "$@.kernel.part" "$@.tmp" && \
+	make_ext4fs -J -L kernel -l "$(LS_SD_KERNELPART_SIZE)M" \
+		$(if $(SOURCE_DATE_EPOCH),-T $(SOURCE_DATE_EPOCH)) \
+		"$@.kernel.part" "$@.tmp" && \
 	dd if=$@.kernel.part >> $@ && \
 	rm -rf $@.tmp && \
 	rm -f $@.kernel.part