scripts/gen_image_generic.sh: move from x86/image

The script can also be useful for other targets.

Signed-off-by: Stijn Tintel <stijn@linux-ipv6.be>

target/linux/x86/image/Makefile

@@ -83,7 +83,7 @@ ifneq ($(CONFIG_GRUB_IMAGES),)
 		-e 's#@TIMEOUT@#$(GRUB_TIMEOUT)#g' \
 		-e 's#@ROOT@#$(GRUB_ROOT)#g' \
 		./grub.cfg > $(KDIR)/root.grub/boot/grub/grub.cfg
-	PADDING="$(CONFIG_TARGET_IMAGES_PAD)" SIGNATURE="$(SIGNATURE)" PATH="$(TARGET_PATH)" ./gen_image_generic.sh \
+	PADDING="$(CONFIG_TARGET_IMAGES_PAD)" SIGNATURE="$(SIGNATURE)" PATH="$(TARGET_PATH)" $(SCRIPT_DIR)/gen_image_generic.sh \
 		$(BIN_DIR)/$(IMG_PREFIX)-combined-$(1).img \
 		$(CONFIG_TARGET_KERNEL_PARTSIZE) $(KDIR)/root.grub \
 		$(CONFIG_TARGET_ROOTFS_PARTSIZE) $(KDIR)/root.$(1) \