Move 'local_tr' function to rc.subr and change its name to 'ltr'.

MFC after:	3 days

etc/rc.d/gbde

@@ -17,27 +17,6 @@ stop_precmd="find_gbde_devices stop"
 start_cmd="gbde_start"
 stop_cmd="gbde_stop"
 
-# Change every ${_src} in ${_str} to ${_dst}.
-# We cannot use tr(1), sed(1) nor awk(1) here, because this script is executed
-# before /usr is mounted.
-local_tr()
-{
-	_str=$1
-	_src=$2
-	_dst=$3
-	_out=""
-
-	IFS=${_src}
-	for _com in ${_str}; do
-		if [ -z "${_out}" ]; then
-			_out="${_com}"
-		else
-			_out="${_out}${_dst}${_com}"
-		fi
-	done
-	echo "${_out}"
-}
-
 find_gbde_devices()
 {
 	case "${gbde_devices-auto}" in
@@ -102,7 +81,7 @@ gbde_start()
 	for device in $gbde_devices; do
 		parent=${device%.bde}
 		parent=${parent#/dev/}
-		parent_=`local_tr ${parent} '/' '_'`
+		parent_=`ltr ${parent} '/' '_'`
 		eval "lock=\${gbde_lock_${parent_}-\"${gbde_lockdir}/${parent_}.lock\"}"
 		if [ -e "/dev/${parent}" -a ! -e "/dev/${parent}.bde" ]; then
 			echo "Configuring Disk Encryption for ${parent}."

etc/rc.subr

@@ -1297,4 +1297,27 @@ mount_md()
 	/sbin/mdmfs $flags -s $1 -M md $2
 }
 
+# ltr str src dst
+#	Change every $src in $str to $dst.
+#	Useful when /usr is not yet mounted and we cannot use tr(1), sed(1) nor
+#	awk(1).
+ltr()
+{
+	local _str _src _dst _out _com
+	_str=$1
+	_src=$2
+	_dst=$3
+	_out=""
+
+	IFS=${_src}
+	for _com in ${_str}; do
+		if [ -z "${_out}" ]; then
+			_out="${_com}"
+		else
+			_out="${_out}${_dst}${_com}"
+		fi
+	done
+	echo "${_out}"
+}
+
 fi