[VP][PDVT-SH] SFC RGB24 output linear-only support

Add SFC RGB24 linear-only output support for new platform.
- Add FtrSFCRGB24OutNoPadding SKU feature flag usage for new platforms
- Set VP_SFC_OUTPUT_SUPPORT_LINEAR_ONLY for Format_R8G8B8 in VP caps
- Fix GetPlaneDefs to use width*3 (not width*4) for Format_R8G8B8 surfaces
- Add SKU-gated hole-stripping logic in VP surface dumper: older SFC inserts
  1 padding byte every 64 bytes in RGB24 output; newer outputs continuous packed
- Extract CopyScanlineWithHoleStripping as a reusable protected method
- Add same hole-stripping logic to postponed command packet path
- Add focus tests for GetPlaneDefs, InitVpVeboxSfcHwCaps, and
  CopyScanlineWithHoleStripping covering both old and new platform paths