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>

     1.1 --- a/config/companion_tools.in	Thu Feb 20 18:23:08 2014 +0000
     1.2 +++ b/config/companion_tools.in	Tue Mar 11 22:11:43 2014 +0100
     1.3 @@ -2,10 +2,14 @@
     1.4  
     1.5  menu "Companion tools"
     1.6  
     1.7 +# Tools that require make-3.81 to build should select this:
     1.8  config COMP_TOOLS_make_3_81_NEEDED
     1.9      bool
    1.10 +
    1.11 +config COMP_TOOLS_FORCE_make_3_81
    1.12 +    def_bool y
    1.13 +    depends on COMP_TOOLS_make_3_81_NEEDED
    1.14      depends on ! CONFIGURE_has_make381
    1.15 -    default y
    1.16      select COMP_TOOLS
    1.17      select COMP_TOOLS_make
    1.18