elf: add prototype for valid_elf_image

Signed-off-by: Jeroen Hofstee <jeroen@myspectrum.nl>

board/w7o/fsboot.c

@@ -8,12 +8,11 @@
 #include <common.h>
 #include <config.h>
 #include <command.h>
+#include <elf.h>
 
 /*
  * FIXME: Add code to test image and it's header.
  */
-extern int valid_elf_image (unsigned long addr);
-
 static int
 image_check(ulong addr)
 {

include/elf.h

@@ -570,4 +570,6 @@ unsigned long elf_hash(const unsigned char *name);
    that may still be in object files.  */
 #define R_PPC_TOC16             255
 
+int valid_elf_image(unsigned long addr);
+
 #endif /* _ELF_H */