[openwrt/openwrt] imagebuilder: fix broken image generation with external targets

[LEDE Commits]

ynezz pushed a commit to openwrt/openwrt.git, branch openwrt-19.07:
https://git.openwrt.org/058c2347c51f4989c325bba03d8a0af19640dced

commit 058c2347c51f4989c325bba03d8a0af19640dced
Author: Petr Štetiar <ynezz at true.cz>
AuthorDate: Thu Mar 24 06:52:37 2022 +0100

    imagebuilder: fix broken image generation with external targets
    
    When using external targets there is a symlink being created for the
    target under target/linux which then becomes dangling under Image
    Builder. Fix it by dereferencing the possible symlink.
    
    Tested on IB with external target, ipq40xx and mvebu.
    
    Signed-off-by: Petr Štetiar <ynezz at true.cz>
    (cherry picked from commit 621f39d1f438bf95dbae667c575926fa16a6d797)
    (cherry picked from commit ec9af870f3278f75549836b469baefa260e2ed41)
    (cherry picked from commit 3008f1f441a41e162311cee1ccadfdaaec1581c1)
---
 target/imagebuilder/Makefile | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/target/imagebuilder/Makefile b/target/imagebuilder/Makefile
index f1f25fc7c4..4246bed1ea 100644
--- a/target/imagebuilder/Makefile
+++ b/target/imagebuilder/Makefile
@@ -57,7 +57,7 @@ else
 	find $(wildcard $(PACKAGE_SUBDIRS)) -type f -name '*.ipk' -exec $(CP) {} $(PKG_BUILD_DIR)/packages/ \;
 endif
 
-	$(CP) $(TOPDIR)/target/linux $(PKG_BUILD_DIR)/target/
+	$(CP) -L $(TOPDIR)/target/linux $(PKG_BUILD_DIR)/target/
 	if [ -d $(TOPDIR)/staging_dir/host/lib/grub ]; then \
 		$(CP) $(TOPDIR)/staging_dir/host/lib/grub/ $(PKG_BUILD_DIR)/staging_dir/host/lib; \
 	fi