parport: remove unused parport_register_device()

All the drivers that are using parallel port has been converted to use
the new device model api, and parport_register_device() is no longer
used.

Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Link: https://lore.kernel.org/r/20200403134325.11523-10-sudipm.mukherjee@gmail.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>