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>

--- a/extra/scripts/unifdef.c

+++ b/extra/scripts/unifdef.c

@@ -206,7 +206,7 @@

 static void             error(const char *);

 static int              findsym(const char *);

 static void             flushline(bool);

-static Linetype         getline(void);

+static Linetype         get_line(void);

 static Linetype         ifeval(const char **);

 static void             ignoreoff(void);

 static void             ignoreon(void);

@@ -512,7 +512,7 @@

 	for (;;) {

 		linenum++;

-		lineval = getline();

+		lineval = get_line();

 		trans_table[ifstate[depth]][lineval]();

 		debug("process %s -> %s depth %d",

 		    linetype_name[lineval],

@@ -526,7 +526,7 @@

  * help from skipcomment().

  */

 static Linetype

-getline(void)

+get_line(void)

 {

 	const char *cp;

 	int cursym;