arch: mips: generic: Add missing of_node_put() in board-ranchu.c

In ranchu_measure_hpt_freq(), of_find_compatible_node() will return
a node pointer with refcount incremented. We should use of_put_node()
when it is not used anymore.

Signed-off-by: Liang He <[e-mail]>
Signed-off-by: Thomas Bogendoerfer <[e-mail]>

arch/mips/generic/board-ranchu.c

···
 		      __func__);
 
 	rtc_base = of_iomap(np, 0);
+	of_node_put(np);
 	if (!rtc_base)
 		panic("%s(): Failed to ioremap Goldfish RTC base!", __func__);