Add xdathread entries for the Nvidia Shield Portable and Tablet

Change-Id: If034af8e24eb19b81c2a9abd5a56940ef7d558c5
diff --git a/_devices/nvidiahshieldportable.markdown b/_devices/nvidiahshieldportable.markdown
index 2d80e38..682e296 100644
--- a/_devices/nvidiahshieldportable.markdown
+++ b/_devices/nvidiahshieldportable.markdown
@@ -8,6 +8,7 @@
 oem: NVidia
 devicetree: https://github.com/TeamWin/android_device_nvidia_roth
 ddof: "/dev/block/platform/sdhci-tegra.3/by-name/SOS"
+xdathread: http://forum.xda-developers.com/nvidia-shield/development/recovery-twrp-shield-portable-t3390017
 ---
 
 {% include disclaimer.html %}
diff --git a/_devices/nvidiahshieldtablet.markdown b/_devices/nvidiahshieldtablet.markdown
index efff4c4..8f5dded 100644
--- a/_devices/nvidiahshieldtablet.markdown
+++ b/_devices/nvidiahshieldtablet.markdown
@@ -8,6 +8,7 @@
 oem: NVidia
 devicetree: https://github.com/TeamWin/android_device_nvidia_shieldtablet
 ddof: "/dev/block/platform/sdhci-tegra.3/by-name/SOS"
+xdathread: http://forum.xda-developers.com/shield-tablet/orig-development/recovery-twrp-2-8-7-0-touch-recovery-t3257172
 ---
 
 {% include disclaimer.html %}