companion_tools/autoconf: add autoconf tool

Initial version of adding autoconf as a companion tool.

Signed-off-by: Richard Strand <richard.strand@icomera.com>
[yann.morin.1998@anciens.enib.fr: use generic overide tools dir]
[yann.morin.1998@anciens.enib.fr: update menu entries]
Signed-off-by: "Yann E. MORIN" <yann.morin.1998@anciens.enib.fr>

--- binutils/ld/ldmain.c

+++ binutils/ld/ldmain.c

@@ -273,2 +273,5 @@ main (int argc, char **argv)

   link_info.emit_hash = TRUE;

+#ifndef __mips__

+  link_info.emit_gnu_hash = TRUE;

+#endif

   link_info.callbacks = &link_callbacks;