prctl: Update PR_GET_TID_ADDR definition

To reflect the change in kernel v3.4-rc4
update PR_GET_TID_ADDR and rename it to
PR_GET_TID_ADDRESS as it named in kernel.

[xemul: this fixes futex test broken with 3.4 rebase]

Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>