staging: gpib: add module descriptions

Every loadable module should have a description, and not having one
causes a W=1 build warning, so add these to the newly added modules.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20241016111521.1143191-2-arnd@kernel.org


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