Custom `sshpass` prompt match (-P flag)

By default, [`sshpass` tries to match the prompt with `assword:`](https://man.archlinux.org/man/extra/sshpass/sshpass.1.en#P), but I need to connect to a server that prompts with `Enter PASSCODE:` Running `sshpass` directly with `-P PASSCODE:` works fine, just need to be able to pass that in from NetworkManager-ssh