HID: playstation: Clamp num_touch_reports

In the Linux kernel, the following vulnerability has been resolved:

HID: playstation: Clamp num_touch_reports

A device would never lie about the number of touch reports would it?

If it does the loop in dualshock4_parse_report will read off the end of

the touch_reports array, up to about 2 KiB for the maximum number of 256

loop iteraions. The data that is read is emitted via evdev if the

DS4_TOUCH_POINT_INACTIVE bit happens to be set. Protect against this by

clamping the num_touch_reports value provided by the device to the

maximum size of the touch_reports array.