mmc: pxamci: Indicate that regulators may be absent

Use regulator_get_optional() to tell the core that requests for regulators
can fail in a real system.

Signed-off-by: Mark Brown <broonie@linaro.org>
Acked-by: Chris Ball <cjb@laptop.org>
diff --git a/drivers/mmc/host/pxamci.c b/drivers/mmc/host/pxamci.c
index 2c5a91b..1956a3d 100644
--- a/drivers/mmc/host/pxamci.c
+++ b/drivers/mmc/host/pxamci.c
@@ -83,7 +83,7 @@
 static inline void pxamci_init_ocr(struct pxamci_host *host)
 {
 #ifdef CONFIG_REGULATOR
-	host->vcc = regulator_get(mmc_dev(host->mmc), "vmmc");
+	host->vcc = regulator_get_optional(mmc_dev(host->mmc), "vmmc");
 
 	if (IS_ERR(host->vcc))
 		host->vcc = NULL;