Add support for `z3s`

[gsmithau]

Is your device already requested?

• I have searched the existing issues

Brand

Samsung

Name

Galaxy S20 Ultra

Device code

Device with code 'z3s' is not supported yet

Model

G988B

Device images

https://wiki.lineageos.org/devices/z3s/
https://twrp.me/samsung/samsunggalaxys20ultra.html

Do you own the device and would be willing to test the installer?

• I own the device and am willing to test the installer on it.

Additional context