mmc: sdhci: Fix parameter of sdhci_do_start_signal_voltage_switch()

3714f4315354 ("mmc: sdhci: update signal voltage switch code") changed the
type of the second parameter of sdhci_do_start_signal_voltage_switch(),
from "struct mmc_ios *ios" to "int signal_voltage" which causes the
following build warning:

drivers/mmc/host/sdhci.c:2044:2: warning: initialization from incompatible pointer type [enabled by default]
drivers/mmc/host/sdhci.c:2044:2: warning: (near initialization for 'sdhci_ops.start_signal_voltage_switch') [enabled by default]

Use the previous type so that it matches the start_signal_voltage_switch()
definition from host.h.
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Reviewed-by: Johan Rudholm <johan.rudholm@stericsson.com>
Signed-off-by: Chris Ball <cjb@laptop.org>

drivers/mmc/host/sdhci.c

@@ -1675,7 +1675,7 @@ static void sdhci_enable_sdio_irq(struct mmc_host *mmc, int enable)
 }
 
 static int sdhci_do_start_signal_voltage_switch(struct sdhci_host *host,
-						int signal_voltage)
+						struct mmc_ios *ios)
 {
 	u16 ctrl;
 	int ret;
@@ -1689,7 +1689,7 @@ static int sdhci_do_start_signal_voltage_switch(struct sdhci_host *host,
 
 	ctrl = sdhci_readw(host, SDHCI_HOST_CONTROL2);
 
-	switch (signal_voltage) {
+	switch (ios->signal_voltage) {
 	case MMC_SIGNAL_VOLTAGE_330:
 		/* Set 1.8V Signal Enable in the Host Control2 register to 0 */
 		ctrl &= ~SDHCI_CTRL_VDD_180;
@@ -1762,7 +1762,7 @@ static int sdhci_do_start_signal_voltage_switch(struct sdhci_host *host,
 }
 
 static int sdhci_start_signal_voltage_switch(struct mmc_host *mmc,
-	int signal_voltage)
+	struct mmc_ios *ios)
 {
 	struct sdhci_host *host = mmc_priv(mmc);
 	int err;
@@ -1770,7 +1770,7 @@ static int sdhci_start_signal_voltage_switch(struct mmc_host *mmc,
 	if (host->version < SDHCI_SPEC_300)
 		return 0;
 	sdhci_runtime_pm_get(host);
-	err = sdhci_do_start_signal_voltage_switch(host, signal_voltage);
+	err = sdhci_do_start_signal_voltage_switch(host, ios);
 	sdhci_runtime_pm_put(host);
 	return err;
 }