uboot-zynq: copy U-Boot images to STAGING_DIR

Create a directory inside STAGING_DIR and copy U-Boot
output images, so they can be used later when creating the
sdcard image

Additionally, like others targets, override the default
install method to avoid copying the images to bin directory

Signed-off-by: Luis Araneda <luaraneda@gmail.com>

package/boot/uboot-zynq/Makefile

@@ -49,6 +49,15 @@ UBOOT_TARGETS := \
 	zybo \
 	zybo_z7
 
+define Build/InstallDev
+	$(INSTALL_DIR) $(STAGING_DIR_IMAGE)
+	$(CP) $(PKG_BUILD_DIR)/spl/boot.bin $(STAGING_DIR_IMAGE)/$(BUILD_DEVICES)-boot.bin
+	$(CP) $(PKG_BUILD_DIR)/u-boot.img $(STAGING_DIR_IMAGE)/$(BUILD_DEVICES)-u-boot.img
+endef
+
+define Package/u-boot/install/default
+endef
+
 Build/Exports:=$(Host/Exports)
 
 $(eval $(call BuildPackage/U-Boot))