mmc: wmt-sdmmc: fix return value check of mmc_add_host()

mmc_add_host() may return error, if we ignore its return value, the memory
that allocated in mmc_alloc_host() will be leaked and it will lead a kernel
crash because of deleting not added device in the remove path.

So fix this by checking the return value and goto error path which will call
mmc_free_host(), besides, clk_disable_unprepare() also needs be called.

Fixes: 3a96dff0 ("mmc: SD/MMC Host Controller for Wondermedia WM8505/WM8650")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Link: https://lore.kernel.org/r/20221101063023.1664968-10-yangyingliang@huawei.comSigned-off-by: Ulf Hansson <ulf.hansson@linaro.org>

drivers/mmc/host/wmt-sdmmc.c

@@ -856,11 +856,15 @@ static int wmt_mci_probe(struct platform_device *pdev)
 	/* configure the controller to a known 'ready' state */
 	wmt_reset_hardware(mmc);
 
-	mmc_add_host(mmc);
+	ret = mmc_add_host(mmc);
+	if (ret)
+		goto fail7;
 
 	dev_info(&pdev->dev, "WMT SDHC Controller initialized\n");
 
 	return 0;
+fail7:
+	clk_disable_unprepare(priv->clk_sdmmc);
 fail6:
 	clk_put(priv->clk_sdmmc);
 fail5_and_a_half: