reset upstream subtrees to HEAD

Reset the following subtrees on HEAD:
  poky: 8217b477a1(master)
  meta-xilinx: 64aa3d35ae(master)
  meta-openembedded: 0435c9e193(master)
  meta-raspberrypi: 490a4441ac(master)
  meta-security: cb6d1c85ee(master)

Squashed patches:
  meta-phosphor: drop systemd 239 patches
  meta-phosphor: mrw-api: use correct install path

Change-Id: I268e2646d9174ad305630c6bbd3fbc1a6105f43d
Signed-off-by: Brad Bishop <bradleyb@fuzziesquirrel.com>
diff --git a/meta-openembedded/meta-networking/README b/meta-openembedded/meta-networking/README
index 7a4aca4..e1ba27d 100644
--- a/meta-openembedded/meta-networking/README
+++ b/meta-openembedded/meta-networking/README
@@ -18,19 +18,19 @@
 This layer depends on:
 
 URI: git://github.com/openembedded/openembedded-core.git
-branch: thud
+branch: master
 revision: HEAD
 
 For some recipes, the meta-oe layer is required:
 
 URI: git://github.com/openembedded/meta-openembedded.git
 subdirectory: meta-oe
-branch: thud
+branch: master
 revision: HEAD
 
 URI: git://github.com/openembedded/meta-openembedded.git
 subdirectory: meta-python
-branch: thud
+branch: master
 revision: HEAD
 
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