package/norm: use external waf

Fixes:
http://autobuild.buildroot.net/results/ee1/ee15cadf8af10dee6c83b9726a034367e8ae81a7/

The bundled waf script is too old (2.0.7) for python >= 3.11 as it uses the
'U' modifier to open (universal newlines), which have been deprecated since
python 3.3 and finally removed in 3.11.

Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/norm/norm.mk

@@ -11,6 +11,9 @@ NORM_INSTALL_STAGING = YES
 NORM_LICENSE = NRL License
 NORM_LICENSE_FILES = LICENSE.TXT
 
+# The bundled waf script is too old for >= python3.11
+NORM_NEEDS_EXTERNAL_WAF = YES
+
 ifeq ($(BR2_PACKAGE_LIBNETFILTER_QUEUE),y)
 NORM_DEPENDENCIES += libnetfilter_queue
 endif