Add the module alias so the rk805-pwrkey driver will
autoload when built as a module.

Fixes: 5a35b85c ("Input: add power key driver for Rockchip RK805 PMIC")
Signed-off-by: Peter Robinson <pbrobinson@gmail.com>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://lore.kernel.org/r/20220612225437.3628788-1-pbrobinson@gmail.comSigned-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>