yweb: fix 'df'-output to determinate space on mtd

Origin commit data
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Commit: a4d82f0ddb
Author: vanhofen <vanhofen@gmx.de>
Date: 2012-07-25 (Wed, 25 Jul 2012)

Origin message was:
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- yweb: fix 'df'-output to determinate space on mtd

src/nhttpd/web/scripts/Y_Tools.sh

@@ -622,8 +622,15 @@ case "$1" in
 			echo "on"
 		fi
 		;;
-	var_space)
-		df |grep mtd2
+	mtd_space|var_space)
+		df | while read fs rest; do
+			case ${fs:0:3} in
+				mtd)
+					echo "$fs" "$rest"
+					break
+				;;
+			esac
+		done
 		;;
 	tmp_space)
 		df /tmp|grep /tmp