HSI: omap_ssi_core: fix possible memory leak in ssi_probe()

If ssi_add_controller() returns error, it should call hsi_put_controller()
to give up the reference that was set in hsi_alloc_controller(), so that
it can call hsi_controller_release() to free controller and ports that
allocated in hsi_alloc_controller().

Fixes: b209e047 ("HSI: Introduce OMAP SSI driver")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>