configure: Test strtoumax() and strtoimax() by linking instead of just compiling (Tru64 fix).
configure: Test strtoumax() and strtoimax() by linking instead of just compiling (Tru64 fix).

damoxc/dovecot,damoxc/dovecot,damoxc/dovecot,damoxc/dovecot,damoxc/dovecot