netcomms: fix bad length for intercept common message

Encryption keys are no longer sent in these messages, just the
encryption type so accounting for the key length in the message
size was incorrect.

Author: salcock

src/netcomms.c

@@ -516,7 +516,6 @@ int push_lea_withdrawal_onto_net_buffer(net_buffer_t *nb, liagency_t *lea) {
          sizeof(common.encrypt) + common.delivcc_len + \
          sizeof(common.time_fmt) + \
          (36 * common.xid_count) + \
-         (common.encryptkey_len ? (common.encryptkey_len + 4) : 0) + \
          ((10 + common.xid_count) * 4))
 
 #define VENDMIRROR_IPINTERCEPT_MODIFY_BODY_LEN(ipint) \