mmc: sdhci: move setting mmc->actual_clock into set_clock handlers

Move the setting of mmc->actual_clock to zero into the set_clock
handlers themselves.  This will allow us to clean up the calling
logic for the set_clock() method, and turn sdhci_set_clock() into
a library function.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Tested-by: Markus Pargmann <mpa@pengutronix.de>
Tested-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Chris Ball <chris@printf.net>
diff --git a/drivers/mmc/host/sdhci-esdhc-imx.c b/drivers/mmc/host/sdhci-esdhc-imx.c
index 1e68a77..ce8939f 100644
--- a/drivers/mmc/host/sdhci-esdhc-imx.c
+++ b/drivers/mmc/host/sdhci-esdhc-imx.c
@@ -600,6 +600,8 @@
 	u32 temp, val;
 
 	if (clock == 0) {
+		host->mmc->actual_clock = 0;
+
 		if (esdhc_is_usdhc(imx_data)) {
 			val = readl(host->ioaddr + ESDHC_VENDOR_SPEC);
 			writel(val & ~ESDHC_VENDOR_SPEC_FRC_SDCLK_ON,