mmc: usdhi6rol0: handle probe deferral for regulator

We ignore errors from mmc_regulator_get_supply() because the usage of
the regulators is optional for the driver, but we still need to check
for and handle EPROBE_DEFER, like it's done in for example dw_mmc.
Otherwise we might end up not using the specified regulators just
because of probe order.
Signed-off-by: Rabin Vincent <rabin.vincent@axis.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

drivers/mmc/host/usdhi6rol0.c

@@ -1715,12 +1715,14 @@ static int usdhi6_probe(struct platform_device *pdev)
 	if (!mmc)
 		return -ENOMEM;
 
+	ret = mmc_regulator_get_supply(mmc);
+	if (ret == -EPROBE_DEFER)
+		goto e_free_mmc;
+
 	ret = mmc_of_parse(mmc);
 	if (ret < 0)
 		goto e_free_mmc;
 
-	mmc_regulator_get_supply(mmc);
-
 	host		= mmc_priv(mmc);
 	host->mmc	= mmc;
 	host->wait	= USDHI6_WAIT_FOR_REQUEST;