drm/i915: Remove user controllable DRM_ERROR for i915_getparam()

The GETPARAM ioctl writes to a user supplied address. If that address is
invalid, it is the user's error and not the driver's, so quietly report
EFAULT and don't blame ourselves with a DRM_ERROR.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1466773227-7994-11-git-send-email-chris@chris-wilson.co.uk

drivers/gpu/drm/i915/i915_drv.c

@@ -752,10 +752,8 @@ static int i915_getparam(struct drm_device *dev, void *data,
 		return -EINVAL;
 	}
 
-	if (copy_to_user(param->value, &value, sizeof(int))) {
-		DRM_ERROR("copy_to_user failed\n");
+	if (put_user(value, param->value))
 		return -EFAULT;
-	}
 
 	return 0;
 }