update-deps: strip -j option

* update-deps: strip -j option from ENV['GNUMAKEFLAGS'], not
  dirstack to get confused by intermingled entering/leaveing
  directory messages.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@61714 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

tool/update-deps

@@ -238,6 +238,10 @@ DEPENDENCIES_SECTION_END_MARK = "\# AUTOGENERATED DEPENDENCIES END\n"
 
 def init_global
   ENV['LC_ALL'] = 'C'
+  if mkflag = ENV['GNUMAKEFLAGS'] and mkflag.sub!(/(\A|\s+)-j\d*(?=\s+|\z)/, '')
+    mkflag.strip!
+    ENV['GNUMAKEFLAGS'] = mkflag
+  end
 
   $opt_fix = false
   $opt_a = false