Improve guard so it works for no eof new line

syntax/dhall.vim

@@ -1,4 +1,5 @@
 if !exists('g:polyglot_disabled') || index(g:polyglot_disabled, 'dhall') == -1
+
 scriptencoding utf-8
 
 if exists('b:current_syntax')
@@ -61,4 +62,5 @@ highlight link dhallComment Comment
 highlight link dhallMultilineComment Comment
 
 let b:current_syntax = 'dhall'
+
 endif