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/poky/bitbake/lib/bb/fetch2/hg.py b/poky/bitbake/lib/bb/fetch2/hg.py
index 936d043..5a2985e 100644
--- a/poky/bitbake/lib/bb/fetch2/hg.py
+++ b/poky/bitbake/lib/bb/fetch2/hg.py
@@ -99,7 +99,7 @@
     def try_premirror(self, ud, d):
         # If we don't do this, updating an existing checkout with only premirrors
         # is not possible
-        if d.getVar("BB_FETCH_PREMIRRORONLY") is not None:
+        if bb.utils.to_boolean(d.getVar("BB_FETCH_PREMIRRORONLY")):
             return True
         if os.path.exists(ud.moddir):
             return False