cc/gcc: disable complibs if not selected

Force gcc to not link with some companion libraries when
there are not needed (because selected-out).

There is no option to tell gcc *not* to build the Graphite and/or
LTO stuff. They *will* be built if gcc finds the suitable companion
libraries. If we do not provide them, but the host has them, then
gcc *will* find them, and link with them.

Consider the following:
- host has suitable PPL and CLooG (eg. Debian Squeeze)
- user wants to build gcc>=4.4
- user de-selects GRAPHITE
- gcc will find the hosts PPL and CLooG, and will use them
- the user moves the toolchain to an older host that does
not have them (eg. Debian Lenny)
- the toolchain fails, when it was properly setup not to

So, explicitly tell gcc *not* to use unneeded companion libs.

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

 diff -durN gcc-4.4.0.orig/gcc/config.gcc gcc-4.4.0/gcc/config.gcc

 --- gcc-4.4.0.orig/gcc/config.gcc	2009-04-17 13:58:41.000000000 +0200

 +++ gcc-4.4.0/gcc/config.gcc	2009-05-27 21:38:31.000000000 +0200

 @@ -2121,7 +2121,7 @@

  	if test x${sh_multilibs} = x ; then

  		case ${target} in

  		sh64-superh-linux* | \

 -		sh[1234]*)	sh_multilibs=${sh_cpu_target} ;;

 +		sh[1234]*)	sh_multilibs=`cd ${srcdir}/config/sh ; echo t-mlib-sh[1-4]* | sed 's:t-mlib-sh:,m:g;s: ::g'` ;;

  		sh64* | sh5*)	sh_multilibs=m5-32media,m5-32media-nofpu,m5-compact,m5-compact-nofpu,m5-64media,m5-64media-nofpu ;;

  		sh-superh-*)	sh_multilibs=m4,m4-single,m4-single-only,m4-nofpu ;;

  		sh*-*-linux*)	sh_multilibs=m1,m3e,m4 ;;