ARM: multi_v7_defconfig: add SDHCI for i.MX

Turn on SDHCI for i.MX support so machines can boot with local rootfs
on SD. Tested on a Wandboard Quad.
Signed-off-by: Olof Johansson <olof@lixom.net>
Reviewed-by: Fabio Estevam <fabio.estevam@freescale.com>

arch/arm/configs/multi_v7_defconfig

@@ -135,6 +135,7 @@ CONFIG_MMC=y
 CONFIG_MMC_ARMMMCI=y
 CONFIG_MMC_SDHCI=y
 CONFIG_MMC_SDHCI_PLTFM=y
+CONFIG_MMC_SDHCI_ESDHC_IMX=y
 CONFIG_MMC_SDHCI_TEGRA=y
 CONFIG_MMC_SDHCI_SPEAR=y
 CONFIG_MMC_OMAP=y