Input: synaptics-rmi4 - unregister function handlers on physical driver registration...

Input: synaptics-rmi4 - unregister function handlers on physical driver registration failure

If rmi_register_physical_driver() fails, the current error path
unregisters only the RMI bus. The function handlers registered
earlier remain registered with the driver core.

Add a separate error path to unregister the function handlers
before unregistering the bus in this failure case.

Fixes: 2b6a321da9a2 ("Input: synaptics-rmi4 - add support for Synaptics RMI4 devices")
Signed-off-by: Haoxiang Li <haoxiang_li2024@163.com>
Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20260610064633.2837084-1-haoxiang_li2024@163.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>