ARM: imx6: add missing put_device() call in imx6q_suspend_init()

if of_find_device_by_node() succeed, imx6q_suspend_init() doesn't have a
corresponding put_device(). Thus add a jump target to fix the exception
handling for this function implementation.

Signed-off-by: yu kuai <yukuai3@huawei.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>