mmc: wbsd: fix return value check of mmc_add_host()

mmc_add_host() may return error, if we ignore its return value,
it will lead two issues:
1. The memory that allocated in mmc_alloc_host() is leaked.
2. In the remove() path, mmc_remove_host() will be called to
   delete device, but it's not added yet, it will lead a kernel
   crash because of null-ptr-deref in device_del().

So fix this by checking the return value and goto error path which
will call mmc_free_host(), besides, other resources also need be
released.

Fixes: 1da177e4 ("Linux-2.6.12-rc2")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Link: https://lore.kernel.org/r/20221109133237.3273558-1-yangyingliang@huawei.comSigned-off-by: Ulf Hansson <ulf.hansson@linaro.org>

drivers/mmc/host/wbsd.c

@@ -1698,7 +1698,17 @@ static int wbsd_init(struct device *dev, int base, int irq, int dma,
 	 */
 	wbsd_init_device(host);
 
-	mmc_add_host(mmc);
+	ret = mmc_add_host(mmc);
+	if (ret) {
+		if (!pnp)
+			wbsd_chip_poweroff(host);
+
+		wbsd_release_resources(host);
+		wbsd_free_mmc(dev);
+
+		mmc_free_host(mmc);
+		return ret;
+	}
 
 	pr_info("%s: W83L51xD", mmc_hostname(mmc));
 	if (host->chip_id != 0)