Now that component has docs it's worth spending a few words and
hyperlinks on recommended best practices in drm.

v2: Add another item that component shouldn't be preferred over
drm_bridge/panel and similar subsystems already providing specialized
support for specific components (Laurent). Also convert to bullet
list.

Cc: Laurent Pinchart
Cc: Russell King - ARM Linux admin
Reviewed-by: Maxime Ripard
Signed-off-by: Daniel Vetter
Link: https://patchwork.freedesktop.org/patch/msgid/20190212164615.13370-1-daniel.vetter@ffwll.ch