drm/i915: remove intel_pipe_set_base() (v4)

After some refactor intel_primary_plane_setplane() does the same
as intel_pipe_set_base() so we can get rid of it and replace the calls
with intel_primary_plane_setplane().

v2: take Ville's comments:
	- get the right arguments for update_plane()
	- use drm_crtc_get_hv_timing()

v3 (by Matt):
 - Rebase to latest di-nightly codebase
 - Use primary->funcs->update_plane() in __intel_set_mode()
 - Use primary->funcs->disable_plane() in intel_crtc_disable()

v4 (by Matt):
 - Drop redundant calls to intel_crtc_wait_for_pending_flips() before
   calling update_plane() (Ville)

Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Acked-and-mourned-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Reviewed-by: Ander Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>