drm/i915: Move plane_state->scaler_id initialization into intel_create_plane_state()

No point in having each caller of intel_create_plane_state() initialize
the scaler_id to -1. Instead just do it in intel_create_plane_state().

Previously we left scaler_id at 0 for pre-SKL platforms, but I can't
see how initializing it to -1 always would cause any harm.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Stanislav Lisovskiy <stanislav.lisovskiy@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20181005125817.22576-8-ville.syrjala@linux.intel.com

drivers/gpu/drm/i915/intel_atomic_plane.c

@@ -56,6 +56,7 @@ intel_create_plane_state(struct drm_plane *plane)
 
 	state->base.plane = plane;
 	state->base.rotation = DRM_MODE_ROTATE_0;
+	state->scaler_id = -1;
 
 	return state;
 }

drivers/gpu/drm/i915/intel_display.c

@@ -13783,8 +13783,6 @@ intel_primary_plane_create(struct drm_i915_private *dev_priv, enum pipe pipe)
 
 	primary->base.state = &state->base;
 
-	if (INTEL_GEN(dev_priv) >= 9)
-		state->scaler_id = -1;
 	primary->pipe = pipe;
 	/*
 	 * On gen2/3 only plane A can do FBC, but the panel fitter and LVDS
@@ -14006,9 +14004,6 @@ intel_cursor_plane_create(struct drm_i915_private *dev_priv,
 						   DRM_MODE_ROTATE_0 |
 						   DRM_MODE_ROTATE_180);
 
-	if (INTEL_GEN(dev_priv) >= 9)
-		state->scaler_id = -1;
-
 	drm_plane_helper_add(&cursor->base, &intel_plane_helper_funcs);
 
 	return cursor;

drivers/gpu/drm/i915/intel_sprite.c

@@ -1821,8 +1821,6 @@ intel_sprite_plane_create(struct drm_i915_private *dev_priv,
 	intel_plane->base.state = &state->base;
 
 	if (INTEL_GEN(dev_priv) >= 9) {
-		state->scaler_id = -1;
-
 		intel_plane->has_ccs = skl_plane_has_ccs(dev_priv, pipe,
 							 PLANE_SPRITE0 + plane);