installrelease.sh overwrites the existing /data/rc.local file

[nc1066]

Describe the bug
Running installrelease.sh overwrites the existing /data/rc.local file. If rc.local is already reloading a custom driver then after the install of the dbus-serialbattery driver the custom driver no longer reloads on reboot.

To Reproduce
run installrelease.sh with an existing /data/rc.local, original contents of rc.local are gone

Expected behavior
Install of dbus-serialbattery driver should not overwrite /data/rc.local

Screenshots
NA

VenusOS:

• Device type: Raspberry Pi 3 model B rev 1.2
• Firmware Version 2.92

Battery/BMS (please complete the following information):

• BMS/Battery type: EG4 Lifepower
• Cells: 8 (24V, 200Ah)
• Interface: USB-RS485

Additional context
I'm loading a custom driver for an Epever CC. I use rc.local to recreate a symbolic link between /service/epever and /data/epever so the Epever CC driver will reload on reboot.