reset upstream subtrees to yocto 2.6

Reset the following subtrees on thud HEAD:

  poky: 87e3a9739d
  meta-openembedded: 6094ae18c8
  meta-security: 31dc4e7532
  meta-raspberrypi: a48743dc36
  meta-xilinx: c42016e2e6

Also re-apply backports that didn't make it into thud:
  poky:
    17726d0 systemd-systemctl-native: handle Install wildcards

  meta-openembedded:
    4321a5d libtinyxml2: update to 7.0.1
    042f0a3 libcereal: Add native and nativesdk classes
    e23284f libcereal: Allow empty package
    030e8d4 rsyslog: curl-less build with fmhttp PACKAGECONFIG
    179a1b9 gtest: update to 1.8.1

Squashed OpenBMC subtree compatibility updates:
  meta-aspeed:
    Brad Bishop (1):
          aspeed: add yocto 2.6 compatibility

  meta-ibm:
    Brad Bishop (1):
          ibm: prepare for yocto 2.6

  meta-ingrasys:
    Brad Bishop (1):
          ingrasys: set layer compatibility to yocto 2.6

  meta-openpower:
    Brad Bishop (1):
          openpower: set layer compatibility to yocto 2.6

  meta-phosphor:
    Brad Bishop (3):
          phosphor: set layer compatibility to thud
          phosphor: libgpg-error: drop patches
          phosphor: react to fitimage artifact rename

    Ed Tanous (4):
          Dropbear: upgrade options for latest upgrade
          yocto2.6: update openssl options
          busybox: remove upstream watchdog patch
          systemd: Rebase CONFIG_CGROUP_BPF patch

Change-Id: I7b1fe71cca880d0372a82d94b5fd785323e3a9e7
Signed-off-by: Brad Bishop <bradleyb@fuzziesquirrel.com>
diff --git a/poky/meta-poky/conf/local.conf.sample b/poky/meta-poky/conf/local.conf.sample
index aa8df40..d28bf58 100644
--- a/poky/meta-poky/conf/local.conf.sample
+++ b/poky/meta-poky/conf/local.conf.sample
@@ -234,12 +234,12 @@
 # Qemu configuration
 #
 # By default qemu will build with a builtin VNC server where graphical output can be
-# seen. The two lines below enable the SDL backend too. By default libsdl-native will
+# seen. The two lines below enable the SDL backend too. By default libsdl2-native will
 # be built, if you want to use your host's libSDL instead of the minimal libsdl built
-# by libsdl-native then uncomment the ASSUME_PROVIDED line below.
+# by libsdl2-native then uncomment the ASSUME_PROVIDED line below.
 PACKAGECONFIG_append_pn-qemu-native = " sdl"
 PACKAGECONFIG_append_pn-nativesdk-qemu = " sdl"
-#ASSUME_PROVIDED += "libsdl-native"
+#ASSUME_PROVIDED += "libsdl2-native"
 
 # CONF_VERSION is increased each time build/conf/ changes incompatibly and is used to
 # track the version of this file when it was generated. This can safely be ignored if