riscv: reduce initrd size for Nezha and LicheeRV boards

The Nezha and the LicheeRV boards do not have enough memory for an initrd
with most modules. Therefore the number of included modules has to be
reduced.

Create file /etc/initramfs-tools/conf.d/modules_list.conf
to set MODULES=list.

Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>

live-build/ubuntu-cpc/hooks.d/base/disk-image-uefi.binary

@@ -267,6 +267,11 @@ install_grub() {
                         chroot mountpoint rm -f /boot/boot.scr
                         ;;
                     "nezha"|"licheerv")
+                        local my_d=$(dirname $(readlink -f ${0}))
+                        echo "Reducing initramfs size for ${SUBARCH} board"
+                        mkdir -p mountpoint/etc/initramfs-tools/conf.d/
+                        cp ${my_d}/initramfs-tools/modules_list.conf mountpoint/etc/initramfs-tools/conf.d/
+                        chroot mountpoint update-initramfs -c -v -k all
                         echo "Installing U-Boot for ${SUBARCH} board"
                         # flash-kernel is needed to install the dtb for update-grub: it uses the
                         # /proc/device-tree/model value to pick the correct dtb and as we are in a chroot,

live-build/ubuntu-cpc/hooks.d/base/initramfs-tools/modules_list.conf

@@ -0,0 +1,6 @@
+# The Nezha and the LicheeRV boards do not have enough memory for an initrd with
+# most modules. Therefore the number of included modules has to be reduced.
+#
+# If further modules are needed, add them to /etc/initramfs-tools/modules.
+
+MODULES=list