silence nm errors during autolib

bin/9l

@@ -63,7 +63,7 @@ then
 			# libthread - we might not be linking with
 			# those object files.
 			a=`
-				nm $PLAN9/lib/lib$i.a |
+				nm $PLAN9/lib/lib$i.a 2>/dev/null |
 				grep '__p9l_autolib_[a-zA-Z0-9+-]*$' |
 				sed 's/.*__p9l_autolib_//' |
 				sort -u |