Add missing voltage input on NCT6796D >From the datasheet: the NCT6796D has 16 voltage readings. Source: NCT6796D_Datasheet_V0_6.pdf page 59-60 This patch adds support for in15 on the NCT6796D. Signed-off-by: Henk Vergonet <henk.vergont@xxxxxxxxx> Patch: https://github.com/torvalds/linux/commit/8ebb8a5d1d02d60a098cdf0bb576f810f307d9df