char: ttyprintk: register console

Register a console in the ttyprintk driver so that it can be selected
for /dev/console with console=ttyprintk on the kernel command line,
similar to other console drivers.

Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com>
Link: https://lore.kernel.org/r/20220215141750.92808-1-vincent.whitchurch@axis.com


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