[source] build: introduce STAGING_DIR_IMAGE

[LEDE Commits]

jow pushed a commit to source.git, branch master:
https://git.lede-project.org/7d57db4d9be2e8c8e72108c0b8702029ba8c70de

commit 7d57db4d9be2e8c8e72108c0b8702029ba8c70de
Author: Jo-Philipp Wich <jo at mein.io>
AuthorDate: Fri Jan 27 13:41:04 2017 +0100

    build: introduce STAGING_DIR_IMAGE
    
    Introduce a new location STAGING_DIR_IMAGE which is intended to be used by
    bootloader iamges and similar image-related artifacts.
    
    This directory is guaranteed to be persistent across kernel upgrades which
    might involve a removal of KERNEL_BUILD_DIR and is guranteed to be bundled
    with the image builder.
    
    Signed-off-by: Jo-Philipp Wich <jo at mein.io>
---
 rules.mk                     | 1 +
 target/imagebuilder/Makefile | 3 +++
 2 files changed, 4 insertions(+)

diff --git a/rules.mk b/rules.mk
index 2586df3..0bd8fde 100644
--- a/rules.mk
+++ b/rules.mk
@@ -152,6 +152,7 @@ STAMP_DIR_HOST=$(BUILD_DIR_HOST)/stamp
 TARGET_ROOTFS_DIR?=$(if $(call qstrip,$(CONFIG_TARGET_ROOTFS_DIR)),$(call qstrip,$(CONFIG_TARGET_ROOTFS_DIR)),$(BUILD_DIR))
 TARGET_DIR:=$(TARGET_ROOTFS_DIR)/root-$(BOARD)
 STAGING_DIR_ROOT:=$(STAGING_DIR)/root-$(BOARD)
+STAGING_DIR_IMAGE:=$(STAGING_DIR)/image
 BUILD_LOG_DIR:=$(TOPDIR)/logs
 PKG_INFO_DIR := $(STAGING_DIR)/pkginfo
 
diff --git a/target/imagebuilder/Makefile b/target/imagebuilder/Makefile
index d891aab..f9dd61c 100644
--- a/target/imagebuilder/Makefile
+++ b/target/imagebuilder/Makefile
@@ -18,6 +18,7 @@ PKG_BUILD_DIR:=$(BUILD_DIR)/$(IB_NAME)
 IB_KDIR:=$(patsubst $(TOPDIR)/%,$(PKG_BUILD_DIR)/%,$(KERNEL_BUILD_DIR))
 IB_LDIR:=$(patsubst $(TOPDIR)/%,$(PKG_BUILD_DIR)/%,$(LINUX_DIR))
 IB_DTSDIR:=$(patsubst $(TOPDIR)/%,$(PKG_BUILD_DIR)/%,$(LINUX_DIR))/arch/$(ARCH)/boot/dts/
+IB_IDIR:=$(patsubst $(TOPDIR)/%,$(PKG_BUILD_DIR)/%,$(STAGING_DIR_IMAGE))
 
 all: compile
 
@@ -78,6 +79,8 @@ endif
 	$(SED) 's,^# REVISION:=.*,REVISION:=$(REVISION),g' $(PKG_BUILD_DIR)/include/version.mk
 	find $(PKG_BUILD_DIR) -name CVS -o -name .git -o -name .svn \
 	  | $(XARGS) rm -rf
+	$(INSTALL_DIR) $(IB_IDIR)
+	-$(CP) $(STAGING_DIR_IMAGE)/* $(IB_IDIR)/
 	$(INSTALL_DIR) $(PKG_BUILD_DIR)/staging_dir/host/bin
 	$(CP) $(STAGING_DIR_HOST)/bin/* $(PKG_BUILD_DIR)/staging_dir/host/bin/
 	(cd $(PKG_BUILD_DIR); find staging_dir/host/bin/ $(IB_LDIR)/scripts/dtc/ -type f | \