apm821xx: fixes WNDAP620 + WNDAP660 sysupgrade failures

OpenWRT on the WNDAP6x0 refuses to sysupgrade to itself
due to a compat_version imbalance. The Image is generated
with version 2.0, but the uci-defaults says that it needs
to be at 3.0 for the device.

Fix this by downgrading WNDAP6x0 05_fix-compat-version's
values back to 2.0 so it matches what we use.

Fixes: 5815884c3a2a ("apm821xx: migrate to DSA")
Signed-off-by: Christian Lamparter <[email protected]>

target/linux/apm821xx/base-files/etc/uci-defaults/05_fix-compat-version

@@ -2,12 +2,15 @@
 
 case "$(board_name)" in
 meraki,mx60|\
-netgear,wndap620|\
-netgear,wndap660|\
 netgear,wndr4700)
 	uci set system.@system[0].compat_version="3.0"
 	uci commit system
 	;;
+netgear,wndap620|\
+netgear,wndap660)
+	uci set system.@system[0].compat_version="2.0"
+	uci commit system
+	;;
 esac
 
 exit 0