esdhc: Detecting 8 bit width before mmc initialization

The upper 4 data signals of esdhc are shared with spi flash.
So detect if the upper 4 pins are assigned to esdhc before
enable sdhc 8 bit width.

Signed-off-by: Haijun Zhang <haijun.zhang@freescale.com>
Acked-by: Pantelis Antoniou <panto@antoniou-consulting.com>
Reviewed-by: York Sun <yorksun@freescale.com>
diff --git a/drivers/mmc/fsl_esdhc.c b/drivers/mmc/fsl_esdhc.c
index f79f167..7b146a3 100644
--- a/drivers/mmc/fsl_esdhc.c
+++ b/drivers/mmc/fsl_esdhc.c
@@ -596,6 +596,11 @@
 	if (caps & ESDHC_HOSTCAPBLT_HSS)
 		mmc->host_caps |= MMC_MODE_HS_52MHz | MMC_MODE_HS;
 
+#ifdef CONFIG_ESDHC_DETECT_8_BIT_QUIRK
+	if (CONFIG_ESDHC_DETECT_8_BIT_QUIRK)
+		mmc->host_caps &= ~MMC_MODE_8BIT;
+#endif
+
 	mmc->f_min = 400000;
 	mmc->f_max = MIN(gd->arch.sdhc_clk, 52000000);