Xiaomi Mi Mix 2: add xda thread

Change-Id: I0473aa99abba9f6adf4dc0d8b86a6999aa2500bc
diff --git a/_xiaomi/xiaomimimix2.markdown b/_xiaomi/xiaomimimix2.markdown
index dc2082c..6507844 100644
--- a/_xiaomi/xiaomimimix2.markdown
+++ b/_xiaomi/xiaomimimix2.markdown
@@ -7,6 +7,7 @@
 maintainer: blankaf
 devicetree: https://github.com/TeamWin/android_device_xiaomi_chiron
 oem: Xiaomi
+xdathread: "https://forum.xda-developers.com/mi-mix-2/development/recovery-twrp-3-2-1-0-xiaomi-mi-mix-2-t3780525"
 ---
 
 {% include disclaimer.html %}