systemd-boot: fixup: bootctl commandline-opts
based on the manpage: https://man.archlinux.org/man/bootctl.1#OPTIONS
--esp-path=
Path to the EFI System Partition (ESP). If not specified, /efi/, /boot/, and /boot/efi/ are
checked in turn. It is recommended to mount the ESP to /efi/, if possible.
Fixes: #292