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 glibc-ports-2.7.orig/sysdeps/unix/sysv/linux/arm/ioperm.c glibc-ports-2.7/sysdeps/unix/sysv/linux/arm/ioperm.c

 --- glibc-2.7.orig/glibc-ports-2.7/sysdeps/unix/sysv/linux/arm/ioperm.c	2005-06-10 13:12:09.000000000 +0200

 +++ glibc-2.7/glibc-ports-2.7/sysdeps/unix/sysv/linux/arm/ioperm.c	2008-05-18 16:19:45.000000000 +0200

 @@ -45,7 +45,6 @@

  #include <sys/mman.h>

  #include <linux/version.h>

 -#include <asm/page.h>

  #include <sys/sysctl.h>

  #define PATH_ARM_SYSTYPE	"/etc/arm_systype"