mmc: sdhci-of-esdhc: Fix refcount leak in esdhc_signal_voltage_switch

[ Upstream commit b5899a3 ]

of_find_matching_node() returns a node pointer with refcount
incremented, we should use of_node_put() on it when not need anymore.
Add missing of_node_put() to avoid refcount leak.
of_node_put() checks null pointer.

Fixes: ea35645 ("mmc: sdhci-of-esdhc: add support for signal voltage switch")
Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
Link: https://lore.kernel.org/r/20220523144255.10310-1-linmq006@gmail.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

drivers/mmc/host/sdhci-of-esdhc.c

@@ -904,6 +904,7 @@ static int esdhc_signal_voltage_switch(struct mmc_host *mmc,
 		scfg_node = of_find_matching_node(NULL, scfg_device_ids);
 		if (scfg_node)
 			scfg_base = of_iomap(scfg_node, 0);
+		of_node_put(scfg_node);
 		if (scfg_base) {
 			sdhciovselcr = SDHCIOVSELCR_TGLEN |
 				       SDHCIOVSELCR_VSELVAL;