[source] oxnas: put u-boot images into image staging directory

[LEDE Commits]

jow pushed a commit to source.git, branch master:
https://git.lede-project.org/7f9d537f21f2bd79a8b5bfd86c50629c76b306dc

commit 7f9d537f21f2bd79a8b5bfd86c50629c76b306dc
Author: Jo-Philipp Wich <jo at mein.io>
AuthorDate: Fri Jan 27 16:21:17 2017 +0100

    oxnas: put u-boot images into image staging directory
    
    Do not put the u-boot images into the kernel build directory as this directory
    might get removed after kernel updates while the u-boot packages InstallDev
    recipe is not getting re-executed because it is still considered current,
    leading to image build failures later on due to missing images.
    
    To ensure that built bootloader images persist over kernel version updates in
    the buildroot, put them into the new STAGING_DIR_IMAGE directory.
    
    Signed-off-by: Jo-Philipp Wich <jo at mein.io>
---
 package/boot/uboot-oxnas/Makefile | 4 ++--
 target/linux/oxnas/image/Makefile | 2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/package/boot/uboot-oxnas/Makefile b/package/boot/uboot-oxnas/Makefile
index 32ee107..daa266e 100644
--- a/package/boot/uboot-oxnas/Makefile
+++ b/package/boot/uboot-oxnas/Makefile
@@ -29,8 +29,8 @@ endef
 UBOOT_TARGETS:=ox820
 
 define Build/InstallDev
-	$(CP) $(PKG_BUILD_DIR)/u-boot.bin \
-		$(KERNEL_BUILD_DIR)/u-boot.bin
+	$(INSTALL_DIR) $(STAGING_DIR_IMAGE)
+	$(CP) $(PKG_BUILD_DIR)/u-boot.bin $(STAGING_DIR_IMAGE)/u-boot.bin
 endef
 
 $(eval $(call BuildPackage/U-Boot))
diff --git a/target/linux/oxnas/image/Makefile b/target/linux/oxnas/image/Makefile
index 7ad0584..bfa0f0c 100644
--- a/target/linux/oxnas/image/Makefile
+++ b/target/linux/oxnas/image/Makefile
@@ -15,7 +15,7 @@ DEVICE_VARS += DTS UBIFS_OPTS
 KERNEL_LOADADDR := 0x60008000
 
 define Build/ubootable
-	(dd if="$(KDIR)/u-boot.bin" bs=128k conv=sync; \
+	(dd if="$(STAGING_DIR_IMAGE)/u-boot.bin" bs=128k conv=sync; \
 	 dd if="$@" bs=128k conv=sync ) >> $@.new
 	@mv "$@.new" "$@"
 endef