Add a udev rule entry for ALUA state changes

[brianatpurestorage]

The Linux kernel has support for this event and will emit an event if a target returns this unit attention.

Add it commented out to match the others in the file.

[e-milne]

Looks fine to me, if for some reason userspace wanted to handle an event. The kernel would automatically update the ALUA state via RTPG if scsi_dh_alua is attached, it doesn't have to be, though.

[tasleson]

Thanks!