Make polkit support optional

This commit modifies the spec file for libvirt to make the inclusion of
support for PolicyKit optional. It is enabled by default to preserve the
existing behavior, but can be disabled by passing `--without-polkit` to
`rpmbuild`.

libvirt.spec

@@ -85,6 +85,7 @@
 %endif
 
 # A few optional bits off by default, we enable later
+%define with_polkit        0%{!?_without_polkit:1}
 %define with_fuse          0%{!?_without_fuse:0}
 %define with_cgconfig      0%{!?_without_cgconfig:0}
 %define with_sanlock       0%{!?_without_sanlock:0}
@@ -361,6 +362,7 @@ BuildRequires: radvd
 BuildRequires: ebtables
 BuildRequires: module-init-tools
 BuildRequires: cyrus-sasl-devel
+%if %{with_polkit}
 %if 0%{?fedora} || 0%{?rhel} >= 7
 # F22 polkit-devel doesn't pull in polkit anymore, which we need for pkcheck
 BuildRequires: polkit >= 0.112
@@ -368,6 +370,7 @@ BuildRequires: polkit-devel >= 0.112
 %else
 BuildRequires: polkit-devel >= 0.93
 %endif
+%endif
 # For mount/umount in FS driver
 BuildRequires: util-linux
 %if %{with_qemu}
@@ -502,11 +505,13 @@ Requires: module-init-tools
 # for /sbin/ip & /sbin/tc
 Requires: iproute
 Requires: avahi-libs
+%if %{with_polkit}
 %if 0%{?fedora} || 0%{?rhel} >= 7
 Requires: polkit >= 0.112
 %else
 Requires: polkit >= 0.93
 %endif
+%endif
 %if %{with_cgconfig}
 Requires: libcgroup
 %endif
@@ -1193,6 +1198,12 @@ exit 1
     %define arg_libxl --without-libxl
 %endif
 
+%if %{with_polkit}
+    %define arg_polkit --with-polkit
+%else
+    %define arg_polkit --without-polkit
+%endif
+
 %if %{with_phyp}
     %define arg_phyp --with-phyp
 %else
@@ -1336,7 +1347,7 @@ rm -f po/stamp-po
            %{?arg_libxl} \
            --with-sasl \
            --with-avahi \
-           --with-polkit \
+           %{?arg_polkit} \
            --with-libvirtd \
            %{?arg_uml} \
            %{?arg_phyp} \
@@ -1858,9 +1869,11 @@ exit 0
 %{_datadir}/augeas/lenses/tests/test_libvirt_lockd.aug
 %endif
 
+%if %{with_polkit}
 %{_datadir}/polkit-1/actions/org.libvirt.unix.policy
 %{_datadir}/polkit-1/actions/org.libvirt.api.policy
 %{_datadir}/polkit-1/rules.d/50-libvirt.rules
+%endif
 
 %dir %attr(0700, root, root) %{_localstatedir}/log/libvirt/
 
@@ -1875,7 +1888,9 @@ exit 0
 %{_mandir}/man8/virtlockd.8*
 %{_mandir}/man7/virkey*.7*
 
+%if %{with_polkit}
 %doc examples/polkit/*.rules
+%endif
 
 %files daemon-config-network
 %dir %{_datadir}/libvirt/networks/