parport: fix a kernel-doc markup

The kernel-doc markup inside share.c is actually for
__parport_register_driver. The actual goal seems to be
to document parport_register_driver().

So, fix the existing markup and add a new one.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/dc0778af8c466cc667409ead05876a5cfd3cbece.1610610937.git.mchehab+huawei@kernel.org


Signed-off-by: Jonathan Corbet <corbet@lwn.net>