mmc: sdhci: add quirk SDHCI_QUIRK_CLOCK_DIV_ZERO_BROKEN

adds quirk for controllers whose clock divider zero is broken,
sdhci_set_clock function will incorporate this modification.

Signed-off-by: Suneel Garapati <suneel.garapati@xilinx.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h
index 5521d29..67046ca 100644
--- a/drivers/mmc/host/sdhci.h
+++ b/drivers/mmc/host/sdhci.h
@@ -409,6 +409,8 @@
 #define SDHCI_QUIRK2_SUPPORT_SINGLE			(1<<13)
 /* Controller broken with using ACMD23 */
 #define SDHCI_QUIRK2_ACMD23_BROKEN			(1<<14)
+/* Broken Clock divider zero in controller */
+#define SDHCI_QUIRK2_CLOCK_DIV_ZERO_BROKEN		(1<<15)
 
 	int irq;		/* Device IRQ */
 	void __iomem *ioaddr;	/* Mapped address */