proc_parse.c: parse_task_cgroup -- Don't forget to init @path

proc_parse.c: In function ‘parse_task_cgroup’:
proc_parse.c:1603:16: error: ‘path’ may be used uninitialized in this function [-Werror=uninitialized]
cc1: all warnings being treated as errors

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