mmc: sdhci: convert sdhci_set_uhs_signaling() into a library function

Add sdhci_set_uhs_signaling() and always call the set_uhs_signaling
method.  This avoids quirks being added into sdhci_set_uhs_signaling().

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>
[Ulf Hansson] Resolved conflict
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Chris Ball <chris@printf.net>

drivers/mmc/host/sdhci-of-arasan.c

@@ -57,6 +57,7 @@ static struct sdhci_ops sdhci_arasan_ops = {
 	.get_timeout_clock = sdhci_arasan_get_timeout_clock,
 	.set_bus_width = sdhci_set_bus_width,
 	.reset = sdhci_reset,
+	.set_uhs_signaling = sdhci_set_uhs_signaling,
 };
 
 static struct sdhci_pltfm_data sdhci_arasan_pdata = {