refactor(scp): rename local var "_dirs{ => _}only" for consistency

Author: akinomyoga

completions/ssh

@@ -535,15 +535,15 @@ _scp_remote_files()
 # @since 2.12
 _comp_xfunc_scp_compgen_local_files()
 {
-    local _dirsonly=""
+    local _dirs_only=""
     if [[ ${1-} == -d ]]; then
-        _dirsonly=set
+        _dirs_only=set
         shift
     fi
 
     local files
     _comp_expand_glob files '"$cur"*' || return 0
-    if [[ $_dirsonly ]]; then
+    if [[ $_dirs_only ]]; then
         _comp_compgen -RU files split -l ${1:+-P "$1"} -- "$(
             command ls -aF1dL "${files[@]}" 2>/dev/null |
                 command sed -e "s/$_comp_cmd_scp__path_esc/\\\\&/g" \