drm/atomic: add connectors_changed to separate it from mode_changed, v2

This can be a separate case from mode_changed, when connectors stay the
same but only the mode is different. Drivers may choose to implement specific
optimizations to prevent a full modeset for this case.

Changes since v1:
- Update kerneldocs slightly.

Cc: dri-devel@lists.freedesktop.org
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Reviewed-by: Ander Conselvan de Oliveira <conselvan2@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index af0bcfe..07cee59 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -413,7 +413,7 @@
 static bool
 needs_modeset(struct drm_crtc_state *state)
 {
-	return state->mode_changed || state->active_changed;
+	return drm_atomic_crtc_needs_modeset(state);
 }
 
 /**