Add fdt_fixup_ethernet helper to set mac addresses

Added a fixup helper that uses aliases to set mac addresses
in the device tree based on the bd_t

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>

include/fdt_support.h

@@ -33,6 +33,7 @@ void do_fixup_by_path(void *fdt, const char *path, const char *prop,
 		      const void *val, int len, int create);
 void do_fixup_by_path_u32(void *fdt, const char *path, const char *prop,
 			  u32 val, int create);
+void fdt_fixup_ethernet(void *fdt, bd_t *bd);
 
 #ifdef CONFIG_OF_HAS_UBOOT_ENV
 int fdt_env(void *fdt);