We will need to extend the structure to keep not only tid/tid_addr
but blocked signals as well, thus rename it to more generic
parasite_dump_thread.

The command PARASITE_CMD_DUMP_TID_ADDR renamed to
PARASITE_CMD_DUMP_THREAD for the same sake.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>