Input: synaptics-rmi4 - fail probing if memory allocation for "phys" fails

While input core can work with input->phys set to NULL userspace might
depend on it, so better fail probing if allocation fails. The system must
be in a pretty bad shape for it to happen anyway.

Signed-off-by: Kunwu Chan <chentao@kylinos.cn>
Link: https://lore.kernel.org/r/20240117073124.143636-1-chentao@kylinos.cn
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>