Solaris: Don't crash when signal handler is called with siginfo_t=NULL.
Solaris: Don't crash when signal handler is called with siginfo_t=NULL.

LTD-Beget/dovecot,LTD-Beget/dovecot,LTD-Beget/dovecot,LTD-Beget/dovecot,LTD-Beget/dovecot