feeds.conf.default: disable management feed

looks like the upstream source packages were un-published.

Signed-off-by: John Crispin <john@phrozen.org>

feeds.conf.default

@@ -2,7 +2,7 @@ src-git packages https://github.com/openwrt/packages.git
 src-git luci https://github.com/openwrt/luci.git
 src-git routing https://github.com/openwrt-routing/packages.git
 src-git telephony https://github.com/openwrt/telephony.git
-src-git management https://github.com/openwrt-management/packages.git
 src-git targets https://github.com/openwrt/targets.git
+#src-git management https://github.com/openwrt-management/packages.git
 #src-git oldpackages http://git.openwrt.org/packages.git
 #src-link custom /usr/src/openwrt/custom-feed