board_f: Add new function to allow runtime DTB selection

Runtime U-boot dtb selection is generally a two step process. First step
is to simply use an initial generic dtb. The second step is to select
the dtb and perhaps execute additional code ones U-boot knows what board
it is running on. Embedded_dtb_select handles the second step by allowing
board specific code to run and perform what ever necessary configuration
that is needed.

Signed-off-by: Franklin S Cooper Jr <fcooper@ti.com>
Reviewed-by: Tom Rini <trini@konsulko.com>

include/common.h

@@ -359,6 +359,10 @@ int get_env_id (void);
 void	pci_init      (void);
 void	pci_init_board(void);
 
+#if defined(CONFIG_DTB_RESELECT)
+int	embedded_dtb_select(void);
+#endif
+
 int	misc_init_f   (void);
 int	misc_init_r   (void);