sdm: Move HPD enable to Primary device Initialization

- Remove enabling HPD on primary power on and do it during
  primary initialization.
- This avoids multiple calls to enable when HDMI is not
  present on the platform.

Change-Id: Ie8738743aea4165bc04cad3d4cecd6c00d791da2
Crs-fixed: 1028341
3 files changed