x86: edison: Enable SD slot

Enable SD slot on Intel Edison platform.

By default firmware doesn't put device on active state. Thus,
we have to do this explicitly.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
diff --git a/board/intel/edison/edison.c b/board/intel/edison/edison.c
index 5faf3c5..d80ee3a 100644
--- a/board/intel/edison/edison.c
+++ b/board/intel/edison/edison.c
@@ -13,9 +13,19 @@
 #include <linux/usb/gadget.h>
 
 #include <asm/cache.h>
+#include <asm/pmu.h>
 #include <asm/scu.h>
 #include <asm/u-boot-x86.h>
 
+/* List of Intel Tangier LSSs */
+#define PMU_LSS_TANGIER_SDIO0_01	1
+
+int board_early_init_r(void)
+{
+	pmu_turn_power(PMU_LSS_TANGIER_SDIO0_01, true);
+	return 0;
+}
+
 static struct dwc3_device dwc3_device_data = {
 	.maximum_speed = USB_SPEED_HIGH,
 	.base = CONFIG_SYS_USB_OTG_BASE,