util: vircgroup: include unistd.h rather than virutil.h

There is nothing in the vircgroup.h header file
requiring virutil.h.

Remove it and include unistd.h in the C files.
Signed-off-by: NJán Tomko <jtomko@redhat.com>
Reviewed-by: NDaniel Henrique Barboza <danielhb413@gmail.com>

src/util/vircgroup.h

@@ -21,7 +21,6 @@
 
 #pragma once
 
-#include "virutil.h"
 #include "virbitmap.h"
 #include "virenum.h"
 

src/util/vircgroupv1.c

@@ -20,6 +20,7 @@
  */
 #include <config.h>
 
+#include <unistd.h>
 #ifdef __linux__
 # include <mntent.h>
 # include <sys/stat.h>

src/util/vircgroupv2.c

@@ -19,6 +19,7 @@
  */
 #include <config.h>
 
+#include <unistd.h>
 #ifdef __linux__
 # include <mntent.h>
 # include <sys/mount.h>