[source] mxs: fix image build issues

[LEDE Commits]

nbd pushed a commit to source.git, branch master:
https://git.lede-project.org/07c9bde0da177754ac5bf0865610b308e080a238

commit 07c9bde0da177754ac5bf0865610b308e080a238
Author: Felix Fietkau <nbd at nbd.name>
AuthorDate: Wed Jan 25 07:31:01 2017 +0100

    mxs: fix image build issues
    
    stage u-boot images in KERNEL_BUILD_DIR for building images
    always select uboot-mxs
    
    Signed-off-by: Felix Fietkau <nbd at nbd.name>
---
 package/boot/uboot-mxs/Makefile | 10 +++++++---
 target/linux/mxs/image/Makefile |  4 ++--
 2 files changed, 9 insertions(+), 5 deletions(-)

diff --git a/package/boot/uboot-mxs/Makefile b/package/boot/uboot-mxs/Makefile
index 66459df..eec7841 100644
--- a/package/boot/uboot-mxs/Makefile
+++ b/package/boot/uboot-mxs/Makefile
@@ -6,6 +6,7 @@
 #
 
 include $(TOPDIR)/rules.mk
+include $(INCLUDE_DIR)/kernel.mk
 
 PKG_VERSION:=2016.01
 PKG_RELEASE:=1
@@ -18,6 +19,8 @@ include $(INCLUDE_DIR)/package.mk
 define U-Boot/Default
   BUILD_TARGET:=mxs
   UBOOT_IMAGE:=u-boot.sb
+  DEFAULT:=y
+  HIDDEN:=1
 endef
 
 define U-Boot/mx23_olinuxino
@@ -32,9 +35,10 @@ UBOOT_TARGETS := \
 	mx23_olinuxino \
 	duckbill
 
-define Build/Compile
-	$(MAKE) -C $(PKG_BUILD_DIR) \
-		CROSS_COMPILE=$(TARGET_CROSS) $(UBOOT_IMAGE)
+UBOOT_MAKE_FLAGS += $(UBOOT_IMAGE)
+
+define Build/InstallDev
+	$(INSTALL_BIN) $(PKG_BUILD_DIR)/$(UBOOT_IMAGE) $(KERNEL_BUILD_DIR)/$(BUILD_VARIANT)-$(UBOOT_IMAGE)
 endef
 
 $(eval $(call BuildPackage/U-Boot))
diff --git a/target/linux/mxs/image/Makefile b/target/linux/mxs/image/Makefile
index 1daa26e..f0f1f6a 100644
--- a/target/linux/mxs/image/Makefile
+++ b/target/linux/mxs/image/Makefile
@@ -40,7 +40,7 @@ define Image/Build/SDCard-vfat-ext4
 
 	./gen_sdcard_vfat_ext4.sh \
 		$(BIN_DIR)/$(2) \
-		$(BIN_DIR)/uboot-mxs-$(4)/uboot-mxs-$(4).sb \
+		$(KDIR)/$(4)-u-boot.sb \
 		$(KDIR)/boot.img \
 		$(KDIR)/root.$(1) \
 		$(CONFIG_TARGET_BOOTFS_PARTSIZE) \
@@ -51,7 +51,7 @@ endef
 define Image/Build/SDCard-ext4-ext4
 	./gen_sdcard_ext4_ext4.sh \
 		$(BIN_DIR)/$(2) \
-		$(BIN_DIR)/uboot-mxs-$(4)/uboot-mxs-$(4).sb \
+		$(KDIR)/$(4)-u-boot.sb \
 		$(KDIR)/root.$(1) \
 		$(CONFIG_TARGET_ROOTFS_PARTSIZE)
 	$(call Image/Gzip,$(BIN_DIR)/$(2))