configure: require libtoolize, create wrapper to it

libtoolize must be checked_for and there needs to be a wrapper
that points to GNU libtoolize since that may be installed
as glibtoolize.
This fixes a problem with building Cloog/PPL that was

Reported-by: "Pierrick Brossin" <pierrick@bs-network.net>
Signed-off-by: "Titus von Boxberg" <titus@v9g.de>
(transplanted from c7c9e98d36d8a6a49fcd5f3836d5797bb965eba7)

--- gcc-4.3.4/libffi/src/arm/sysv.S	

+++ gcc-4.3.4/libffi/src/arm/sysv.S	

@@ -235,7 +235,7 @@ ARM_FUNC_START ffi_closure_SYSV

 	stmfd	sp!, {ip, lr}

 	UNWIND .save	{r0, lr}

 	add	r2, sp, #8

-	.pad #16

+	UNWIND .pad #16

 	sub	sp, sp, #16

 	str	sp, [sp, #8]

 	add	r1, sp, #8