drm/i915: Prefer to use the pipe to index the ddb entries

Let's use the pipe rather than the silly 'i' iterator from
for_each_oldnew_intel_crtc_in_state() for indexing the ddb
entries array. Maybe one day we can assume c99 and hide the
'i' entirely from sight.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200115190813.17971-3-ville.syrjala@linux.intel.comReviewed-by: José Roberto de Souza <jose.souza@intel.com>

drivers/gpu/drm/i915/display/intel_display.c

@@ -15106,15 +15106,17 @@ static void skl_commit_modeset_enables(struct intel_atomic_state *state)
 	int i;
 
 	for_each_oldnew_intel_crtc_in_state(state, crtc, old_crtc_state, new_crtc_state, i) {
+		enum pipe pipe = crtc->pipe;
+
 		if (!new_crtc_state->hw.active)
 			continue;
 
 		/* ignore allocations for crtc's that have been turned off. */
 		if (!needs_modeset(new_crtc_state)) {
-			entries[i] = old_crtc_state->wm.skl.ddb;
-			update_pipes |= BIT(crtc->pipe);
+			entries[pipe] = old_crtc_state->wm.skl.ddb;
+			update_pipes |= BIT(pipe);
 		} else {
-			modeset_pipes |= BIT(crtc->pipe);
+			modeset_pipes |= BIT(pipe);
 		}
 	}
 
@@ -15140,10 +15142,10 @@ static void skl_commit_modeset_enables(struct intel_atomic_state *state)
 				continue;
 
 			if (skl_ddb_allocation_overlaps(&new_crtc_state->wm.skl.ddb,
-							entries, num_pipes, i))
+							entries, num_pipes, pipe))
 				continue;
 
-			entries[i] = new_crtc_state->wm.skl.ddb;
+			entries[pipe] = new_crtc_state->wm.skl.ddb;
 			update_pipes &= ~BIT(pipe);
 
 			intel_update_crtc(crtc, state, old_crtc_state,
@@ -15178,9 +15180,9 @@ static void skl_commit_modeset_enables(struct intel_atomic_state *state)
 			continue;
 
 		WARN_ON(skl_ddb_allocation_overlaps(&new_crtc_state->wm.skl.ddb,
-						    entries, num_pipes, i));
+						    entries, num_pipes, pipe));
 
-		entries[i] = new_crtc_state->wm.skl.ddb;
+		entries[pipe] = new_crtc_state->wm.skl.ddb;
 		modeset_pipes &= ~BIT(pipe);
 
 		if (is_trans_port_sync_mode(new_crtc_state)) {
@@ -15213,9 +15215,9 @@ static void skl_commit_modeset_enables(struct intel_atomic_state *state)
 			continue;
 
 		WARN_ON(skl_ddb_allocation_overlaps(&new_crtc_state->wm.skl.ddb,
-						    entries, num_pipes, i));
+						    entries, num_pipes, pipe));
 
-		entries[i] = new_crtc_state->wm.skl.ddb;
+		entries[pipe] = new_crtc_state->wm.skl.ddb;
 		modeset_pipes &= ~BIT(pipe);
 
 		intel_update_crtc(crtc, state, old_crtc_state, new_crtc_state);