poky: set MAINTAINER clearly

The default Poky-specific MAINTAINER assignment makes it look like the
maintainer is a person called Poky.

Instead, use "Poky Maintainers" as the name.

(From meta-yocto rev: 8e17aeb3fd3246ae59119e3e1c693a4f9a3b3420)

Signed-off-by: Ross Burton <ross.burton@arm.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta-poky/conf/distro/poky.conf

@@ -6,7 +6,7 @@ SDK_VENDOR = "-pokysdk"
 SDK_VERSION = "${@d.getVar('DISTRO_VERSION').replace('snapshot-${METADATA_REVISION}', 'snapshot')}"
 SDK_VERSION[vardepvalue] = "${SDK_VERSION}"
 
-MAINTAINER = "Poky <poky@lists.yoctoproject.org>"
+MAINTAINER = "Poky Maintainers <poky@lists.yoctoproject.org>"
 
 TARGET_VENDOR = "-poky"