configs/: remove "Copy to RAM" boot entries since it is automatic now
The default is now copytoram=auto
.
See https://gitlab.archlinux.org/mkinitcpio/mkinitcpio-archiso/-/issues/13 and https://gitlab.archlinux.org/mkinitcpio/mkinitcpio-archiso/-/merge_requests/26.
Implements #177 (closed).