extcon: arizona: Rename hpdet_ip to make its purpose clearer

Renamed to hpdet_ip_version to make it clearer what it does
and that the value in it is simply a version number.

Signed-off-by: Richard Fitzgerald <rf@opensource.wolfsonmicro.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>