mmc: sdhci-bcm2835: Staticize bcm2835_sdhci_get_min_clock

'bcm2835_sdhci_get_min_clock' is used only in this file.
Make it static.

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
diff --git a/drivers/mmc/host/sdhci-bcm2835.c b/drivers/mmc/host/sdhci-bcm2835.c
index 0584a1c..36fa2df 100644
--- a/drivers/mmc/host/sdhci-bcm2835.c
+++ b/drivers/mmc/host/sdhci-bcm2835.c
@@ -119,7 +119,7 @@
 	return byte;
 }
 
-unsigned int bcm2835_sdhci_get_min_clock(struct sdhci_host *host)
+static unsigned int bcm2835_sdhci_get_min_clock(struct sdhci_host *host)
 {
 	return MIN_FREQ;
 }