Fix memset invocation in mod_skypopen

We were previously clearing a pointer's worth of memory rather than
clearing a full element.

This also fixes the build as gcc-4.8 catches this error.

src/mod/endpoints/mod_skypopen/skypopen_protocol.c

@@ -522,7 +522,7 @@ int skypopen_signaling_read(private_t *tech_pvt)
 								 tech_pvt->chatmessages[i].from_handle, tech_pvt->chatmessages[i].from_dispname, tech_pvt->chatmessages[i].body);
 							if (strcmp(tech_pvt->chatmessages[i].from_handle, tech_pvt->skype_user)) {	//if the message was not sent by myself
 								incoming_chatmessage(tech_pvt, i);
-								memset(&tech_pvt->chatmessages[i], '\0', sizeof(&tech_pvt->chatmessages[i]));
+								memset(&tech_pvt->chatmessages[i], '\0', sizeof(tech_pvt->chatmessages[i]));
 
 								sprintf(msg_to_skype, "SET CHATMESSAGE %s SEEN", id);
 								skypopen_signaling_write(tech_pvt, msg_to_skype);
@@ -531,7 +531,7 @@ int skypopen_signaling_read(private_t *tech_pvt)
 									("CHATMESSAGE %s is in position %d in the chatmessages array, type=%s, id=%s, chatname=%s, from_handle=%s, from_dispname=%s, body=%s NOT DELETED\n",
 									 SKYPOPEN_P_LOG, id, i, tech_pvt->chatmessages[i].type, tech_pvt->chatmessages[i].id, tech_pvt->chatmessages[i].chatname,
 									 tech_pvt->chatmessages[i].from_handle, tech_pvt->chatmessages[i].from_dispname, tech_pvt->chatmessages[i].body);
-								memset(&tech_pvt->chatmessages[i], '\0', sizeof(&tech_pvt->chatmessages[i]));
+								memset(&tech_pvt->chatmessages[i], '\0', sizeof(tech_pvt->chatmessages[i]));
 								DEBUGA_SKYPE("chatmessage %s HAS BEEN DELETED\n", SKYPOPEN_P_LOG, id);
 							}