ramips: mt7620: disable images for Netgear 2700

Because openwrt-ramips-mt7620-netgear_ex2700-squashfs-factory.bin is too big.

Signed-off-by: Petr Štetiar <[email protected]>

target/linux/ramips/image/mt7620.mk

@@ -611,6 +611,7 @@ define Device/netgear_ex2700
   DEVICE_VENDOR := NETGEAR
   DEVICE_MODEL := EX2700
   SUPPORTED_DEVICES += ex2700
+  DEFAULT := n
 endef
 TARGET_DEVICES += netgear_ex2700