Move D-Bus policy file to /usr/share/dbus-1/system.d/

To better support stateless systems with an empty /etc, the old location
in /etc/dbus-1/system.d/ should only be used for local admin changes.
Package provided D-Bus policy files are supposed to be installed in
/usr/share/dbus-1/system.d/.

This is supported since dbus 1.9.18.

https://lists.freedesktop.org/archives/dbus/2015-July/016746.html
1 job for dbus-policy in 3 minutes and 37 seconds
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passed #3656437
build_stable

00:03:37