tegra2: Enable MMC for Seaboard

This adds the required GPIO and pinmux configuration to make eMMC / SD work
on Seaboard.

Signed-off-by: Simon Glass <sjg@chromium.org>
Tested-by: Tom Warren <twarren@nvidia.com>
diff --git a/board/nvidia/common/board.c b/board/nvidia/common/board.c
index 5ba7bda..d13537d 100644
--- a/board/nvidia/common/board.c
+++ b/board/nvidia/common/board.c
@@ -160,6 +160,7 @@
 	/* Enable clocks, muxes, etc. for SDMMC controllers */
 	clock_init_mmc();
 	pin_mux_mmc();
+	gpio_config_mmc();
 
 	debug("board_mmc_init: init eMMC\n");
 	/* init dev 0, eMMC chip, with 4-bit bus */
@@ -171,18 +172,6 @@
 
 	return 0;
 }
-
-/* this is a weak define that we are overriding */
-int board_mmc_getcd(u8 *cd, struct mmc *mmc)
-{
-	debug("board_mmc_getcd called\n");
-	/*
-	 * Hard-code CD presence for now. Need to add GPIO inputs
-	 * for Seaboard & Harmony (& Kaen/Aebl/Wario?)
-	 */
-	*cd = 1;
-	return 0;
-}
 #endif
 
 #ifdef CONFIG_BOARD_EARLY_INIT_F