poky.conf: bump version for 4.0.26

(From meta-yocto rev: 3dd438c749099f2a5e808c4690d7ea767263e5b5)

Signed-off-by: Steve Sakoman <steve@sakoman.com>

meta-poky/conf/distro/poky.conf

@@ -1,7 +1,7 @@
 DISTRO = "poky"
 DISTRO_NAME = "Poky (Yocto Project Reference Distro)"
 #DISTRO_VERSION = "3.4+snapshot-${METADATA_REVISION}"
-DISTRO_VERSION = "4.0.25"
+DISTRO_VERSION = "4.0.26"
 DISTRO_CODENAME = "kirkstone"
 SDK_VENDOR = "-pokysdk"
 SDK_VERSION = "${@d.getVar('DISTRO_VERSION').replace('snapshot-${METADATA_REVISION}', 'snapshot')}"