comptools: do not force build of make-3.81 unless really needed

On systems with make-3.82, we forcibly force the build and the use
of make-3.81

But some newer tools break when building with make-3.81. For example,
eglibc-3.18 breaks.

Introduce a new blind options that tools may select if they require
make-3.81. If the system does not have make-3.81, and this option is
selected, then we force the build of make-3.81. Otherwise, we leave
it to the user to decide on his own.

Note that no component selects this option for now. It will come in
later patches as we find them.

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>

--- a/bfd/elf32-arm.c

+++ b/bfd/elf32-arm.c

@@ -12408,7 +12408,8 @@ elf32_arm_check_relocs (bfd *abfd, struc

 	  /* If the symbol is a function that doesn't bind locally,

 	     this relocation will need a PLT entry.  */

-	  root_plt->refcount += 1;

+	  if (root_plt->refcount != -1)

+	    root_plt->refcount += 1;

 	  if (!call_reloc_p)

 	    arm_plt->noncall_refcount++;