hwspinlock: qcom_hwspinlock: add missing of_node_put after calling of_parse_phandle

of_node_put needs to be called when the device node which is got
from of_parse_phandle has finished using.

Cc: [e-mail]
Cc: [e-mail]
Signed-off-by: Peter Chen <[e-mail]>
Signed-off-by: Bjorn Andersson <[e-mail]>

drivers/hwspinlock/qcom_hwspinlock.c

···
 	}
 
 	regmap = syscon_node_to_regmap(syscon);
+	of_node_put(syscon);
 	if (IS_ERR(regmap))
 		return PTR_ERR(regmap);