add fy-NL and lt to the firefox build, l10n only

browser/locales/all-locales

@@ -11,6 +11,7 @@ es-ES
 eu
 fi
 fr
+fy-NL
 ga-IE
 gu-IN
 he
@@ -20,11 +21,12 @@ it
 ja
 ja-JP-mac
 ko
+lt
+mk
+mn
 nb-NO
 nl
 nn-NO
-mk
-mn
 pa-IN
 pl
 pt-BR