msm8226: Disable SDHCI HS400 mode for MSM8226

Use target specific config option to disable HS400 mode.

Change-Id: Ic45f62a5975948e2482a9b791f51e506e73c4df2
diff --git a/target/msm8226/init.c b/target/msm8226/init.c
index e9bac7e..b90c9a7 100644
--- a/target/msm8226/init.c
+++ b/target/msm8226/init.c
@@ -216,6 +216,7 @@
 	config.sdhc_base = mmc_sdhci_base[config.slot - 1];
 	config.pwrctl_base = mmc_pwrctl_base[config.slot - 1];
 	config.pwr_irq     = mmc_sdc_pwrctl_irq[config.slot - 1];
+	config.hs400_support = 0;
 
 	if (!(dev = mmc_init(&config)))
 	{