Input: synaptics-rmi4 - fix function name in kerneldoc

No functional modification involved.

drivers/input/rmi4/rmi_bus.c:300: warning: expecting prototype for rmi_register_function_handler(). Prototype was for __rmi_register_function_handler() instead.

Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Link: https://lore.kernel.org/r/20230209040710.111456-1-jiapeng.chong@linux.alibaba.com


Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>