reset: fix reset_control_get_exclusive kerneldoc comment

Add missing parentheses to correctly hyperlink the reference to
reset_control_get_shared().

Fixes: 0b52297f ("reset: Add support for shared reset controls")
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>

include/linux/reset.h

@@ -143,7 +143,7 @@ static inline int device_reset_optional(struct device *dev)
  * If this function is called more than once for the same reset_control it will
  * return -EBUSY.
  *
- * See reset_control_get_shared for details on shared references to
+ * See reset_control_get_shared() for details on shared references to
  * reset-controls.
  *
  * Use of id names is optional.