Improve guard so it works for no eof new line

syntax/dcov.vim

@@ -1,4 +1,5 @@
 if !exists('g:polyglot_disabled') || index(g:polyglot_disabled, 'dlang') == -1
+
 " Vim syntax file for coverage information for the reference compiler (DMD) of
 " the D programming language.
 "
@@ -50,4 +51,5 @@ hi def link dcovLow                     Operator
 hi def link dcovPartial                 Structure
 
 let b:current_syntax = "dcov"
+
 endif