zdtm_ct: call setsid() to move in another autogroup

Transition and streaming tests can create many processes
which are using cpu. CPU should be divided between tests fairly.
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

test/zdtm_ct.c

@@ -20,6 +20,11 @@ int main(int argc, char **argv)
 		return 1;
 	pid = fork();
 	if (pid == 0) {
+		if (setsid() == -1) {
+			fprintf(stderr, "setsid: %m\n");
+			return 1;
+		}
+
 		if (mount(NULL, "/", NULL, MS_REC | MS_PRIVATE, NULL)) {
 			fprintf(stderr, "mount(/, S_REC | MS_PRIVATE)): %m");
 			return 1;