mediatek: filogic: D-Link M30/M60: include initramfs in recovery

mediatek: filogic: D-Link M30/M60: include initramfs in recovery

Currently, if OEM recovery flashes OpenWrt to second ubi1,
OpenWrt cannot boot. With this commit, recovery image is built
with initramfs kernel, so that it can boot from either ubi or ubi1.

This adds an extra step to OpenWrt installation from OEM:
user needs to sysupgrade from initramfs to full system.

Signed-off-by: Mateusz Krzak <kszaquitto+github@gmail.com>
Link: https://github.com/openwrt/openwrt/pull/18878
(cherry picked from commit 6615c8cfc85f1373cf93a9fc08cb1cb3bbefc964)
Signed-off-by: Mateusz Krzak <kszaquitto+github@gmail.com>
Link: https://github.com/openwrt/openwrt/pull/19595
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>