use system zlib

dkarm-eabi/scripts/build-gcc.sh

@@ -59,6 +59,7 @@ then
 		--with-headers=../../newlib-$NEWLIB_VER/newlib/libc/include \
 		--prefix=$prefix \
 		--enable-lto $plugin_ld\
+		--with-system-zlib \
 		--with-bugurl="http://wiki.devkitpro.org/index.php/Bug_Reports" --with-pkgversion="devkitARM release 46" \
 		$CROSS_PARAMS \
 		|| { echo "Error configuring gcc"; exit 1; }