make a zedboot USB key
usage: fx mkzedboot-remote HOST [DIR] [--no-build] [--no-check-ssh-keys] --usb USB_DEVICE [--force]
--no-build do not build, just pull artifacts already present
--no-check-ssh-keys do not verify that the default SSH credentials are the
same before paving.
HOST the hostname to connect to
DIR defaults to ${HOME}/fuchsia, the path to the FUCHSIA_DIR on HOST
--force force writing to a non-usb target
HOST and DIR are persisted in the file //.fx-remote-config and are reused as
defaults in future invocations of any 'fx *-remote' tools.