Drop removal of firewall4 package for I2SE Duckbill device.
With OPKG the firewall4 package was installed anyway as it's a
dependency of luci-app-firewall and was silently installed again later
in such condition. Drop it to fix support for APK.
Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
f9afff8b28