mount: set is_ns_root on dump

It is required to not dump content of the root mount in dump_one_fd().

travis-ci: success for Fix a few issues to dump/restore Docker containers with userns
Signed-off-by: Andrei Vagin <avagin@virtuozzo.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

criu/proc_parse.c

@@ -37,6 +37,7 @@
 #include "cgroup.h"
 #include "cgroup-props.h"
 #include "timerfd.h"
+#include "path.h"
 
 #include "protobuf.h"
 #include "images/fdinfo.pb-c.h"
@@ -1318,6 +1319,7 @@ static int parse_mountinfo_ent(char *str, struct mount_info *new, char **fsname)
 	if (!new->mountpoint)
 		goto err;
 	new->ns_mountpoint = new->mountpoint;
+	new->is_ns_root = is_root(new->ns_mountpoint + 1);
 
 	new->s_dev = new->s_dev_rt = MKKDEV(kmaj, kmin);
 	new->flags = 0;