drm/panel: Changes for v4.3-rc1

This introduces support for a couple of new panels and also contains
some work to restructure the directories to get more consistency, to
deal better with more panel and bridge drivers getting added.

* tag 'drm/panel/for-4.3-rc1' of git://anongit.freedesktop.org/tegra/linux:
  drm/bridge: Put Kconfig entries in a separate menu
  drm/panel: Add support for LG LG4573 480x800 4.3" panel
  drm/panel: Add display timing for Okaya RS800480T-7X0GP
  of: Add Okaya Electric America vendor prefix
  drm/panel: simple: Add support for NEC NL4827HC19-05B 480x272 panel
  drm/panel: simple: Add support for AUO B080UAN01
  drm/panel: simple: Correct minimum hsync length of the HannStar HSD070PWW1 panel
  drm/panel: simple: Add bus format for HannStar HSD070PWW1 LVDS panel
  drm/bridge: Add vendor prefixes
  drm/panel: Add Samsung prefix to panel drivers
  drm/exynos: Remove PTN3460 dependency