'previewheight' is global-only, don't imply otherwise

Author: ches

plugin/vim-erlang-tags.vim

@@ -88,10 +88,10 @@ endfunction
 
 " Because :pedit can't take height as count like :split does, ugh why.
 function! s:ExecWithPreviewHeight(cmd, height)
-    let orig_height = &l:previewheight
-    let &l:previewheight = a:height
+    let orig_height = &previewheight
+    let &previewheight = a:height
     execute a:cmd
-    let &l:previewheight = orig_height
+    let &previewheight = orig_height
 endfunction
 
 function! VimErlangTagsDefineMappings()