drm/i915/mocs: use to_gt() instead of direct &i915->gt

Have to give up the const on i915 pointer, but it's not big of a deal
considering non-const i915 gets passed all over the place.
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Gustavo Sousa <gustavo.sousa@intel.com>
Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com>
Acked-by: Michał Winiarski <michal.winiarski@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/63e644f056c7745eb0e8e165c990c392a38ec85c.1696236329.git.jani.nikula@intel.com

drivers/gpu/drm/i915/gt/intel_mocs.c

@@ -487,7 +487,7 @@ static bool has_mocs(const struct drm_i915_private *i915)
 	return !IS_DGFX(i915);
 }
 
-static unsigned int get_mocs_settings(const struct drm_i915_private *i915,
+static unsigned int get_mocs_settings(struct drm_i915_private *i915,
 				      struct drm_i915_mocs_table *table)
 {
 	unsigned int flags;
@@ -495,7 +495,7 @@ static unsigned int get_mocs_settings(const struct drm_i915_private *i915,
 	memset(table, 0, sizeof(struct drm_i915_mocs_table));
 
 	table->unused_entries_index = I915_MOCS_PTE;
-	if (IS_GFX_GT_IP_RANGE(&i915->gt0, IP_VER(12, 70), IP_VER(12, 71))) {
+	if (IS_GFX_GT_IP_RANGE(to_gt(i915), IP_VER(12, 70), IP_VER(12, 71))) {
 		table->size = ARRAY_SIZE(mtl_mocs_table);
 		table->table = mtl_mocs_table;
 		table->n_entries = MTL_NUM_MOCS_ENTRIES;