New Holland T6 seat suspension

[Thefarmer91]

Seat suspension of New Holland T6 not work! cab suspension is ok.

[Skunkworks]

Please add this to known issues.

- PC/Mac/PS4/XB1: PC and XBox One
- Vehicle/Tool/Model/Object: New Holland T6
- Issue: Seat suspension not working
- Single- or Multiplayer: Single
- Steps to reproduce: Drive around
- Does it happen on a standard map without mods yes/no Yes