tty: simplify sysctl registration

register_sysctl_table() is a deprecated compatibility wrapper.
register_sysctl_init() can do the directory creation for you so just use
that

Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Link: https://lore.kernel.org/r/20230302204612.782387-7-mcgrof@kernel.org


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