academic/arpack: Disable parallel build.

Signed-off-by: B. Watson <yalhcru@gmail.com>

Signed-off-by: Willy Sudiarto Raharjo <willysr@slackbuilds.org>

academic/arpack/arpack.SlackBuild

@@ -88,6 +88,9 @@ find -L . \
  \( -perm 666 -o -perm 664 -o -perm 600 -o -perm 444 -o -perm 440 -o -perm 400 \) \
  -exec chmod 644 {} \;
 
+# Disable parallel building otherwise build fails
+MAKEFLAGS=-j1
+
 mkdir static shared
 cd shared
 for dir in ../SRC ../UTIL; do