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>

Original patch from: ../crosstool-NG/ct-ng.trunk/patches/binutils/2.19/180-libiberty-pic.patch

-= BEGIN original header =-

Original patch from Gentoo:

gentoo/src/patchsets/binutils/2.19/91_all_libiberty-pic.patch

-= END original header =-

diff -durN binutils-2.19.1.orig/libiberty/Makefile.in binutils-2.19.1/libiberty/Makefile.in

--- binutils-2.19.1.orig/libiberty/Makefile.in	2008-07-24 15:51:49.000000000 +0200

+++ binutils-2.19.1/libiberty/Makefile.in	2009-03-08 11:57:03.000000000 +0100

@@ -227,6 +227,7 @@

 	  $(AR) $(AR_FLAGS) $(TARGETLIB) \

 	    $(REQUIRED_OFILES) $(EXTRA_OFILES) $(LIBOBJS); \

 	  $(RANLIB) $(TARGETLIB); \

+	  cp $(TARGETLIB) ../ ; \

 	  cd ..; \

 	else true; fi