drm/i915: Make i915_destroy_error_state take dev_priv

Since it does not need dev at all.

Also change the stored pointer in struct i915_error_state_file_priv
to i915.

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>

drivers/gpu/drm/i915/i915_sysfs.c

@@ -535,7 +535,7 @@ static ssize_t error_state_read(struct file *filp, struct kobject *kobj,
 	if (ret)
 		return ret;
 
-	error_priv.dev = dev;
+	error_priv.i915 = dev_priv;
 	i915_error_state_get(dev, &error_priv);
 
 	ret = i915_error_state_to_str(&error_str, &error_priv);
@@ -560,7 +560,7 @@ static ssize_t error_state_write(struct file *file, struct kobject *kobj,
 	struct drm_i915_private *dev_priv = kdev_minor_to_i915(kdev);
 
 	DRM_DEBUG_DRIVER("Resetting error state\n");
-	i915_destroy_error_state(&dev_priv->drm);
+	i915_destroy_error_state(dev_priv);
 
 	return count;
 }