ARM: omap5: add ft_board_setup for dra7xx/am57xx

Adds the board specific ft_board_setup() functions that
are called when CONFIG_OF_BOARD_SETUP is defined. These functions
will currently just call the ft_cpu_setup() function.

Adds CONFIG_OF_BOARD_SETUP to the defconfig files
for dra72_evm, dra74_evm, and am57xx_evm.

Signed-off-by: Daniel Allred <d-allred@ti.com>
Signed-off-by: Madan Srinivas <madans@ti.com>

Reviewed-by: Tom Rini <trini@konsulko.com>
diff --git a/board/ti/am57xx/board.c b/board/ti/am57xx/board.c
index 86b8f6e..9904047 100644
--- a/board/ti/am57xx/board.c
+++ b/board/ti/am57xx/board.c
@@ -686,3 +686,12 @@
 	return 0;
 }
 #endif
+
+#if defined(CONFIG_OF_LIBFDT) && defined(CONFIG_OF_BOARD_SETUP)
+int ft_board_setup(void *blob, bd_t *bd)
+{
+	ft_cpu_setup(blob, bd);
+
+	return 0;
+}
+#endif