qualcommax: ipq807x: add Netgear DEVICE_VARS

Add NETGEAR_BOARD_ID and NETGEAR_HW_ID to DEVICE_VARS as multiple devices
set them in their recipes, so without them being added to DEVICE_VARS then
simply the value from last recipe that gets evaluated is used and images
are generated with the wrong ID-s.

Link: https://github.com/openwrt/openwrt/pull/17203
Signed-off-by: Robert Marko <[email protected]>
(cherry picked from commit 1b6f7ec6794233fbf7c1cf17dcee34053c08fa9c)

target/linux/qualcommax/image/ipq807x.mk

@@ -1,3 +1,5 @@
+DEVICE_VARS += NETGEAR_BOARD_ID NETGEAR_HW_ID
+
 define Build/asus-fake-ramdisk
 	rm -rf $(KDIR)/tmp/fakerd
 	dd if=/dev/zero bs=32 count=1 > $(KDIR)/tmp/fakerd