https://bugzilla.redhat.com/show_bug.cgi?id=863576

Bug Description: Abandon of a Simple Paged Results request causes
the self deadlock.  When abandoning a simple paged result request,
the mutex for the connection object c_mutex is locked in do_abandon.
But to free a pagedresult massage id, pagedresults_free_one_msgid
called from do_abandon tries to acquire lock on c_mutex again.
The NSPR lock function PR_Lock is not self re-entrant.  Thus the
server hangs there due to the self-deadlock.

Fix Description: This patch is removing to call PR_Lock(c_mutex)
in pagedresults_free_one_msgid and renamed it to pagedresults_free_
one_msgid_nolock.  To maintain the consistency, "_nolock" is added
to other pagedresults apis which do not call PR_Lock in it.
Also, stricter locking on c_mutex is being added to pagedresults_
parse_control_value to protect the pagedresults related field in
the connection object.