am57xx: add support for cape detect functionality

This commit enables using the extension board detection mechanism on
AM57xx based platforms.

Signed-off-by: Kory Maincent <kory.maincent@bootlin.com>
diff --git a/arch/arm/mach-omap2/omap5/Kconfig b/arch/arm/mach-omap2/omap5/Kconfig
index a7132da..4c2f990 100644
--- a/arch/arm/mach-omap2/omap5/Kconfig
+++ b/arch/arm/mach-omap2/omap5/Kconfig
@@ -36,6 +36,7 @@
 	select CMD_DDR3
 	select DRA7XX
 	select TI_I2C_BOARD_DETECT
+	select SUPPORT_EXTENSION_SCAN
 	imply DM_THERMAL
 	imply SCSI
 	imply SPL_THERMAL
diff --git a/board/ti/am57xx/board.c b/board/ti/am57xx/board.c
index 73063fa..05c26c7 100644
--- a/board/ti/am57xx/board.c
+++ b/board/ti/am57xx/board.c
@@ -43,6 +43,7 @@
 #include <hang.h>
 
 #include "../common/board_detect.h"
+#include "../common/cape_detect.h"
 #include "mux_data.h"
 
 #ifdef CONFIG_SUPPORT_EMMC_BOOT