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/distro/poky.conf b/poky/meta-poky/conf/distro/poky.conf
index fb9e783..7e6fe13 100644
--- a/poky/meta-poky/conf/distro/poky.conf
+++ b/poky/meta-poky/conf/distro/poky.conf
@@ -1,7 +1,7 @@
 DISTRO = "poky"
 DISTRO_NAME = "Poky (Yocto Project Reference Distro)"
-DISTRO_VERSION = "2.5.2"
-DISTRO_CODENAME = "sumo"
+DISTRO_VERSION = "2.6"
+DISTRO_CODENAME = "thud"
 SDK_VENDOR = "-pokysdk"
 SDK_VERSION := "${@'${DISTRO_VERSION}'.replace('snapshot-${DATE}','snapshot')}"
 
@@ -21,7 +21,7 @@
 
 DISTRO_FEATURES ?= "${DISTRO_FEATURES_DEFAULT} ${DISTRO_FEATURES_LIBC} ${POKY_DEFAULT_DISTRO_FEATURES}"
 
-PREFERRED_VERSION_linux-yocto ?= "4.14%"
+PREFERRED_VERSION_linux-yocto ?= "4.18%"
 
 SDK_NAME = "${DISTRO}-${TCLIBC}-${SDK_ARCH}-${IMAGE_BASENAME}-${TUNE_PKGARCH}"
 SDKPATH = "/opt/${DISTRO}/${SDK_VERSION}"
@@ -64,16 +64,17 @@
 CONNECTIVITY_CHECK_URIS ?= "https://www.example.com/"
 
 SANITY_TESTED_DISTROS ?= " \
-            poky-2.4 \n \
             poky-2.5 \n \
-            ubuntu-15.04 \n \
+            poky-2.6 \n \
             ubuntu-16.04 \n \
-            ubuntu-18.04 \n \
-            fedora-28 \n \
+            ubuntu-16.10 \n \
+            ubuntu-17.04 \n \
+            fedora-26 \n \
             centos-7 \n \
             debian-8 \n \
             debian-9 \n \
-            opensuse-42.3 \n \
+            opensuse-42.1 \n \
+            opensuse-42.2 \n \
             "
 #
 # OELAYOUT_ABI allows us to notify users when the format of TMPDIR changes in
@@ -89,11 +90,12 @@
 # QA check settings - a little stricter than the OE-Core defaults
 WARN_TO_ERROR_QA = "already-stripped compile-host-path install-host-path \
                     installed-vs-shipped ldflags pn-overrides rpaths staticdev \
-                    useless-rpaths"
+                    unknown-configure-option useless-rpaths"
 WARN_QA_remove = "${WARN_TO_ERROR_QA}"
 ERROR_QA_append = " ${WARN_TO_ERROR_QA}"
 
 require conf/distro/include/poky-world-exclude.inc
 require conf/distro/include/no-static-libs.inc
 require conf/distro/include/yocto-uninative.inc
+require conf/distro/include/security_flags.inc
 INHERIT += "uninative"