lrmd (LF 1715): increase the max dispatch time for lrmd

A simple change to increase the warning limit for dispatch time
from 30ms to 300ms. Other files had to be changed because
set_sigchld_proctrack() got additional parameter. However, they
remained functionally/semantically the same. See also:

http://old.linux-foundation.org/developer_bugzilla/show_bug.cgi?id=1715

Mercurial revision: aaa8b66a2afd6107c2a0015bb8fe91c2df24f9f9