[openwrt/openwrt] ath79: fix parallel image generation for Zyxel NBG6716

[LEDE Commits]

adrian pushed a commit to openwrt/openwrt.git, branch master:
https://git.openwrt.org/766d1d675baf332251d0d80a11e835eeb05ada11

commit 766d1d675baf332251d0d80a11e835eeb05ada11
Author: André Valentin <avalentin at marcant.net>
AuthorDate: Fri Sep 17 21:48:55 2021 +0200

    ath79: fix parallel image generation for Zyxel NBG6716
    
    This changes the image generation to use a unique directory. With
    parallel building it may occur that two concurrent jobs try
    to create an image which leds to errors. It also removes a needless
    subdirecory.
    
    Signed-off-by: André Valentin <avalentin at marcant.net>
---
 target/linux/ath79/image/nand.mk | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/target/linux/ath79/image/nand.mk b/target/linux/ath79/image/nand.mk
index 52631789d9..8d3d2ce5b2 100644
--- a/target/linux/ath79/image/nand.mk
+++ b/target/linux/ath79/image/nand.mk
@@ -1,13 +1,12 @@
 # attention: only zlib compression is allowed for the boot fs
 define Build/zyxel-buildkerneljffs
-	rm -rf  $(KDIR_TMP)/zyxelnbg6716
-	mkdir -p $(KDIR_TMP)/zyxelnbg6716/image/boot
-	cp $@ $(KDIR_TMP)/zyxelnbg6716/image/boot/vmlinux.lzma.uImage
+	mkdir -p $@.tmp/boot
+	cp $@ $@.tmp/boot/vmlinux.lzma.uImage
 	$(STAGING_DIR_HOST)/bin/mkfs.jffs2 \
 		--big-endian --squash-uids -v -e 128KiB -q -f -n -x lzma -x rtime \
 		-o $@ \
-		-d $(KDIR_TMP)/zyxelnbg6716/image
-	rm -rf $(KDIR_TMP)/zyxelnbg6716
+		-d $@.tmp
+	rm -rf $@.tmp
 endef
 
 define Build/zyxel-factory