How to use Huawei Update Extractor
fastboot flash cust cust.img fastboot flash boot boot.img fastboot flash recovery RECOVERY.IMG fastboot flash system system.img fastboot flash cache cache.img fastboot flash userdata userdata.img
References
http://forum.xda-developers.com/showthread.php?t=2433454
http://www.needrom.com/download/huawei-ascend-mate-7-mt7-l09/
http://www.daviddosa.nhely.hu/en/2016/04/05/using-huawei-update-extractor/
https://boycracked.com/2016/02/12/easy-guide-to-unbrick-update-firmware-any-android-devices-via-fastboot-mode/