ALSA: hda/conexant: Fix missing error check for jack detection

In the Linux kernel, the following vulnerability has been resolved: ALSA: hda/conexant: Fix missing error check for jack detection In cx_probe(), the return value of snd_hda_jack_detect_enable_callback() is ignored. This function returns a pointer, and if it fails (e.g., due to memory allocation failure), it returns an error pointer which must be checked using IS_ERR(). If the registration fails, the driver continues to probe, but the jack detection callback will not be registered. This can lead to a kernel crash later when the driver attempts to handle jack events or accesses the uninitialized structure. Check the return value using IS_ERR() and propagate the error via PTR_ERR() to the probe caller.