augenrules: use ls from $PATH

We already use rm and mktemp from $PATH, it makes
little sense to use an absolute path just for `ls`.
It is part of coreutils too.

Author: LordGrimmauld

init.d/augenrules

@@ -83,7 +83,7 @@ fi
 #   - the last processed -e directive is emitted as the last line
 umask 0137
 echo "## This file is automatically generated from $SourceRulesDir" >> "${TmpRules}"
-for rules in $(/bin/ls -1v ${SourceRulesDir} | grep "\.rules$") ; do
+for rules in $(ls -1v ${SourceRulesDir} | grep "\.rules$") ; do
 	cat ${SourceRulesDir}/"${rules}"
 done | awk '
 BEGIN   {