regulator: core: Fix default return value for _get()

Now that we are defaulting to providing dummy regulators fix the logic
for substituting a dummy by making the default return code -EPROBE_DEFER.
Reported-by: NThierry Reding <treding@nvidia.com>
Tested-by: NThierry Reding <treding@nvidia.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

drivers/regulator/core.c

@@ -1247,7 +1247,7 @@ static struct regulator *_regulator_get(struct device *dev, const char *id,
 	struct regulator_dev *rdev;
 	struct regulator *regulator = ERR_PTR(-EPROBE_DEFER);
 	const char *devname = NULL;
-	int ret = 0;
+	int ret = -EPROBE_DEFER;
 
 	if (id == NULL) {
 		pr_err("get() with no identifier\n");