mmc: sdhci-esdhc-imx: clear f_max in boarddata

After commit 8d86e4fccc ("mmc: sdhci-esdhc-imx: Call mmc_of_parse()"),
it's not used anymore.

Signed-off-by: Dong Aisheng <aisheng.dong@freescale.com>
Reviewed-by: Johan Derycke <johan.derycke@barco.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

drivers/mmc/host/sdhci-esdhc-imx.c

@@ -581,13 +581,8 @@ static void esdhc_writeb_le(struct sdhci_host *host, u8 val, int reg)
 static unsigned int esdhc_pltfm_get_max_clock(struct sdhci_host *host)
 {
 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
-	struct pltfm_imx_data *imx_data = pltfm_host->priv;
-	struct esdhc_platform_data *boarddata = &imx_data->boarddata;
 
-	if (boarddata->f_max && (boarddata->f_max < pltfm_host->clock))
-		return boarddata->f_max;
-	else
-		return pltfm_host->clock;
+	return pltfm_host->clock;
 }
 
 static unsigned int esdhc_pltfm_get_min_clock(struct sdhci_host *host)