Add _image_binary_end section declaration

This is used in some link scripts, so add a declaration for it.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>

include/asm-generic/sections.h

@@ -82,6 +82,7 @@ extern ulong __data_end;
 extern ulong __rel_dyn_start;
 extern ulong __rel_dyn_end;
 extern ulong __bss_end;
+extern ulong _image_binary_end;
 
 extern ulong _TEXT_BASE;	/* code start */