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/meta-openembedded/meta-python/recipes-devtools/python/python-attrs.inc b/meta-openembedded/meta-python/recipes-devtools/python/python-attrs.inc
index c29f058..fa73ea5 100644
--- a/meta-openembedded/meta-python/recipes-devtools/python/python-attrs.inc
+++ b/meta-openembedded/meta-python/recipes-devtools/python/python-attrs.inc
@@ -3,8 +3,8 @@
 LICENSE = "MIT"
 LIC_FILES_CHKSUM = "file://LICENSE;md5=d4ab25949a73fe7d4fdee93bcbdbf8ff"
 
-SRC_URI[md5sum] = "d7a89063b2e0fd36bd82389c4d82821d"
-SRC_URI[sha256sum] = "1c7960ccfd6a005cd9f7ba884e6316b5e430a3f1a6c37c5f87d8b43f83b54ec9"
+SRC_URI[sha256sum] = "e0d0eb91441a3b53dab4d9b743eafc1ac44476296a2053b6ca3af0b139faf87b"
+SRC_URI[md5sum] = "3f3f3e0750dab74cfa1dc8b0fd7a5f86"
 
 inherit pypi