phosphor-base.inc: remove old pygobject PREFERRED_VERSION

We do not use pygobject any more and the PREFERRED_VERSION does
not even exist (python2-based).

Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
Change-Id: I620fb8202dd2fc72ab8b9c3b6b63237f3b714ed8
diff --git a/conf/distro/include/phosphor-base.inc b/conf/distro/include/phosphor-base.inc
index 8d53c8d..297b2d3 100644
--- a/conf/distro/include/phosphor-base.inc
+++ b/conf/distro/include/phosphor-base.inc
@@ -124,9 +124,6 @@
 
 DISTRO_EXTRA_RDEPENDS_remove_qemuarm = "packagegroup-core-device-devel"
 
-# TODO: openbmc/openbmc#12345 - Upgrade to pygobject-3.
-PREFERRED_VERSION_python-pygobject = "2.%"
-
 include conf/distro/include/openbmc-phosphor/${MACHINE}.inc
 
 KERNEL_FEATURES_append = " phosphor-gpio-keys"