drm/i915: Constify adjusted_mode

Make adjusted_mode const whereever we don't have to modify it. This only
covers cases when we have a local adjusted_mode variable, and doesn't
make any difference for cases where we just dereference
pipe_config->adjusted_mode.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Mika Kahola <mika.kahola@intel.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 5105e09..47bf13f 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -4392,7 +4392,7 @@
 int skl_update_scaler_crtc(struct intel_crtc_state *state)
 {
 	struct intel_crtc *intel_crtc = to_intel_crtc(state->base.crtc);
-	struct drm_display_mode *adjusted_mode = &state->base.adjusted_mode;
+	const struct drm_display_mode *adjusted_mode = &state->base.adjusted_mode;
 
 	DRM_DEBUG_KMS("Updating scaler for [CRTC:%i] scaler_user index %u.%u\n",
 		      intel_crtc->base.base.id, intel_crtc->pipe, SKL_CRTC_INDEX);
@@ -6477,7 +6477,7 @@
 				       struct intel_crtc_state *pipe_config)
 {
 	struct drm_device *dev = intel_crtc->base.dev;
-	struct drm_display_mode *adjusted_mode = &pipe_config->base.adjusted_mode;
+	const struct drm_display_mode *adjusted_mode = &pipe_config->base.adjusted_mode;
 	int lane, link_bw, fdi_dotclock, ret;
 	bool needs_recompute = false;
 
@@ -6556,7 +6556,7 @@
 {
 	struct drm_device *dev = crtc->base.dev;
 	struct drm_i915_private *dev_priv = dev->dev_private;
-	struct drm_display_mode *adjusted_mode = &pipe_config->base.adjusted_mode;
+	const struct drm_display_mode *adjusted_mode = &pipe_config->base.adjusted_mode;
 
 	/* FIXME should check pixel clock limits on all platforms */
 	if (INTEL_INFO(dev)->gen < 4) {
@@ -7624,7 +7624,7 @@
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	enum pipe pipe = intel_crtc->pipe;
 	enum transcoder cpu_transcoder = intel_crtc->config->cpu_transcoder;
-	struct drm_display_mode *adjusted_mode = &intel_crtc->config->base.adjusted_mode;
+	const struct drm_display_mode *adjusted_mode = &intel_crtc->config->base.adjusted_mode;
 	uint32_t crtc_vtotal, crtc_vblank_end;
 	int vsyncshift = 0;