Input: tps6507x-ts - remove vref from platform data

Although defined in platform data, vref is not used anywhere.

Also remove model, irq, and clear_penirq as they are not used either.

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

input: Touchscreen driver for TPS6507x

Add touch screen input driver for TPS6507x family of multi-function
chips. Uses the TPS6507x MFD driver. No interrupt support due to
testing limitations of current hardware.

Signed-off-by: Todd Fischer <todd.fischer@ridgerun.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>