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>

 diff -durN gcc-3.4.6.orig/gcc/config/sh/sh.h gcc-3.4.6/gcc/config/sh/sh.h

 --- gcc-3.4.6.orig/gcc/config/sh/sh.h	2006-01-12 02:20:32.000000000 +0100

 +++ gcc-3.4.6/gcc/config/sh/sh.h	2007-08-15 23:03:09.000000000 +0200

 @@ -422,6 +422,10 @@

  do {									\

    if (LEVEL)								\

      flag_omit_frame_pointer = -1;					\

 +  if (LEVEL <= 2)							\

 +    {									\

 +      flag_reorder_blocks = 0;						\

 +    }									\

    if (SIZE)								\

      target_flags |= SPACE_BIT;						\

    if (TARGET_SHMEDIA && LEVEL > 1)					\