build: move elecom-wrc-gs-factory to image-commands.mk

ELECOM WRC-X3200GST3 uses the same header/footer as WRC-GS/GST devices
in ramips/mt7621 subtarget, so move "Build/elecom-wrc-gs-factory" to
image-commands.mk to use from mediatek/mt7622 subtarget.

Signed-off-by: INAGAKI Hiroshi <musashino.open@gmail.com>

include/image-commands.mk

@@ -187,6 +187,19 @@ define Build/elecom-product-header
 	mv $(fw).new $(fw)
 endef
 
+define Build/elecom-wrc-gs-factory
+	$(eval product=$(word 1,$(1)))
+	$(eval version=$(word 2,$(1)))
+	$(eval hash_opt=$(word 3,$(1)))
+	$(MKHASH) md5 $(hash_opt) $@ >> $@
+	( \
+		echo -n "ELECOM $(product) v$(version)" | \
+			dd bs=32 count=1 conv=sync; \
+		dd if=$@; \
+	) > $@.new
+	mv $@.new $@
+endef
+
 define Build/elx-header
 	$(eval hw_id=$(word 1,$(1)))
 	$(eval xor_pattern=$(word 2,$(1)))

target/linux/ramips/image/mt7621.mk

@@ -9,19 +9,6 @@ DEFAULT_SOC := mt7621
 KERNEL_DTB += -d21
 DEVICE_VARS += ELECOM_HWNAME LINKSYS_HWNAME
 
-define Build/elecom-wrc-gs-factory
-	$(eval product=$(word 1,$(1)))
-	$(eval version=$(word 2,$(1)))
-	$(eval hash_opt=$(word 3,$(1)))
-	$(MKHASH) md5 $(hash_opt) $@ >> $@
-	( \
-		echo -n "ELECOM $(product) v$(version)" | \
-			dd bs=32 count=1 conv=sync; \
-		dd if=$@; \
-	) > $@.new
-	mv $@.new $@
-endef
-
 define Build/gemtek-trailer
 	printf "%s%08X" ".GEMTEK." "$$(cksum $@ | cut -d ' ' -f1)" >> $@
 endef