How to modify the "/init.rc" file

[dubis]

Hi everyone,

I would like to modify the "/init.rc", in adding this line :

symlink /system/bin /bin

I know these king of files are coming from the "initramfs" boot image (see the link). That meaning they're coming from an image and if you modified them the modification are lost at the next reboot.
I would like to do that because I observed an error message in my crond log as example :

crond: child running /bin/sh
crond: can't execute '/bin/sh' for user root
crond: USER root pid 9466 cmd date >> /sdcard/LastDaterecord

That could mean the link is needed, in this case would to know which boot partition I've to modified :

ls -l /dev/block/platform/d0074000.emmc/ <
lrwxrwxrwx root root 2015-01-01 00:00 boot -> /dev/block/boot
lrwxrwxrwx root root 2015-01-01 00:00 bootloader -> /dev/block/bootloader
drwxr-xr-x root root 2015-01-01 00:00 by-num
lrwxrwxrwx root root 2015-01-01 00:00 cache -> /dev/block/cache
lrwxrwxrwx root root 2015-01-01 00:00 crypt -> /dev/block/crypt
lrwxrwxrwx root root 2015-01-01 00:00 data -> /dev/block/data
lrwxrwxrwx root root 2015-01-01 00:00 env -> /dev/block/env
lrwxrwxrwx root root 2015-01-01 00:00 instaboot -> /dev/block/instaboot
lrwxrwxrwx root root 2015-01-01 00:00 logo -> /dev/block/logo
lrwxrwxrwx root root 2015-01-01 00:00 misc -> /dev/block/misc
lrwxrwxrwx root root 2015-01-01 00:00 mmcblk0 -> /dev/block/mmcblk0
lrwxrwxrwx root root 2015-01-01 00:00 mmcblk0boot0 -> /dev/block/mmcblk0boot0
lrwxrwxrwx root root 2015-01-01 00:00 mmcblk0boot1 -> /dev/block/mmcblk0boot1
lrwxrwxrwx root root 2015-01-01 00:00 mmcblk0rpmb -> /dev/block/mmcblk0rpmb
lrwxrwxrwx root root 2015-01-01 00:00 recovery -> /dev/block/recovery
lrwxrwxrwx root root 2015-01-01 00:00 reserved -> /dev/block/reserved
lrwxrwxrwx root root 2015-01-01 00:00 rsv -> /dev/block/rsv
lrwxrwxrwx root root 2015-01-01 00:00 system -> /dev/block/system
lrwxrwxrwx root root 2015-01-01 00:00 tee -> /dev/block/tee

Note, I bricked the original system on my TV player which is a Leelbox S1 S905X 1G+8G. For fix it, I flashed it with the nexbox_a95x Android 6.0.1 20161118 image pack I found on this forum. That could help for knowing how the partition table is managed. My system is working well since. However, I'm not able to restore an original system because the USB is not found by Windows 10 and Amlogic USB Burning Tool v2.0.8 doesn't find the device also, in plan B case.

Thanks for your help.