mmc: omap_hsmmc: Handle failure of regulator_get better.

1/ If regulator_get fails, return an error.  This is important if
   it failed with EPROBE_DEFER, as the probe needs to be deferred.

2/ Don't set .set_power until the regulator has been found, or
   the deferred probe will not bother calling omap_hsmmc_reg_get().
Signed-off-by: NeilBrown <neilb@suse.de>
Acked-by: Rajendra Nayak <rnayak@ti.com>
Signed-off-by: Chris Ball <cjb@laptop.org>

drivers/mmc/host/omap_hsmmc.c

@@ -301,12 +301,12 @@ static int omap_hsmmc_reg_get(struct omap_hsmmc_host *host)
 	struct regulator *reg;
 	int ocr_value = 0;
 
-	mmc_slot(host).set_power = omap_hsmmc_set_power;
-
 	reg = regulator_get(host->dev, "vmmc");
 	if (IS_ERR(reg)) {
 		dev_dbg(host->dev, "vmmc regulator missing\n");
+		return PTR_ERR(reg);
 	} else {
+		mmc_slot(host).set_power = omap_hsmmc_set_power;
 		host->vcc = reg;
 		ocr_value = mmc_regulator_get_ocrmask(reg);
 		if (!mmc_slot(host).ocr_mask) {