drm/i915: Use helper func to find out map type

Use i915_coherent_map_type() function to find out
map_type of the shmem obj.

v2: handle non-llc platform(Matt)
Signed-off-by: Nirmoy Das <nirmoy.das@intel.com>
Reviewed-by: Andrzej Hajda <andrzej.hajda@intel.com>
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221219112933.21417-1-nirmoy.das@intel.com

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

@@ -8,6 +8,7 @@
 #include <linux/pagemap.h>
 #include <linux/shmem_fs.h>
 
+#include "i915_drv.h"
 #include "gem/i915_gem_object.h"
 #include "gem/i915_gem_lmem.h"
 #include "shmem_utils.h"
@@ -32,6 +33,8 @@ struct file *shmem_create_from_data(const char *name, void *data, size_t len)
 
 struct file *shmem_create_from_object(struct drm_i915_gem_object *obj)
 {
+	struct drm_i915_private *i915 = to_i915(obj->base.dev);
+	enum i915_map_type map_type;
 	struct file *file;
 	void *ptr;
 
@@ -41,8 +44,8 @@ struct file *shmem_create_from_object(struct drm_i915_gem_object *obj)
 		return file;
 	}
 
-	ptr = i915_gem_object_pin_map_unlocked(obj, i915_gem_object_is_lmem(obj) ?
-						I915_MAP_WC : I915_MAP_WB);
+	map_type = i915_coherent_map_type(i915, obj, true);
+	ptr = i915_gem_object_pin_map_unlocked(obj, map_type);
 	if (IS_ERR(ptr))
 		return ERR_CAST(ptr);