qemu-cgroup: remove unnecessary include

The file doesn't use virSystemd functions directly.
Signed-off-by: NMarc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: NMichal Privoznik <mprivozn@redhat.com>

src/qemu/qemu_cgroup.c

@@ -36,7 +36,6 @@
 #include "virfile.h"
 #include "virtypedparam.h"
 #include "virnuma.h"
-#include "virsystemd.h"
 #include "virdevmapper.h"
 #include "virutil.h"