Escaping leading '.' in cgroup names

Escaping a leading '.' with '_' in the cgroup names
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>
(cherry picked from commit 0ced83dc)

src/util/vircgroup.c

@@ -1118,7 +1118,8 @@ static int virCgroupPartitionNeedsEscaping(const char *path)
     if (STRPREFIX(path, "cgroup."))
         return 1;
 
-    if (path[0] == '_')
+    if (path[0] == '_' ||
+        path[0] == '.')
         return 1;
 
     if (!(fp = fopen("/proc/cgroups", "r")))