load_vposer bugs fixed

[SajjadAemmi]

• load_vposer bugs fixed
• fix deprecated add_

[y-71]

I have

Traceback (most recent call last):
  File "D:\work\gem\smpl\smplify-x\smplifyx\main.py", line 269, in <module>
    main(**args)
  File "D:\work\gem\smpl\smplify-x\smplifyx\main.py", line 183, in main
    body_pose_prior = body_pose_prior.to(device=device)
AttributeError: 'function' object has no attribute 'to'

[SajjadAemmi]

@y-71 thank you for your feedback, please test again.