mfd: cros_ec_dev: Fix cros_feature_to_{name,cells} struct descriptions

Kerneldoc expects kernel structures to be prefixed with 'struct'.

Fixes the following W=1 level warnings:

 drivers/mfd/cros_ec_dev.c:32: warning: cannot understand function prototype: 'struct cros_feature_to_name '
 drivers/mfd/cros_ec_dev.c:44: warning: cannot understand function prototype: 'struct cros_feature_to_cells '

Cc: Benson Leung <bleung@chromium.org>
Cc: Guenter Roeck <groeck@chromium.org>
Cc: Bill Richardson <wfrichar@chromium.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Acked-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

drivers/mfd/cros_ec_dev.c

@@ -24,7 +24,7 @@ static struct class cros_class = {
 };
 
 /**
- * cros_feature_to_name - CrOS feature id to name/short description.
+ * struct cros_feature_to_name - CrOS feature id to name/short description.
  * @id: The feature identifier.
  * @name: Device name associated with the feature id.
  * @desc: Short name that will be displayed.
@@ -36,7 +36,7 @@ struct cros_feature_to_name {
 };
 
 /**
- * cros_feature_to_cells - CrOS feature id to mfd cells association.
+ * struct cros_feature_to_cells - CrOS feature id to mfd cells association.
  * @id: The feature identifier.
  * @mfd_cells: Pointer to the array of mfd cells that needs to be added.
  * @num_cells: Number of mfd cells into the array.