Clear mouse hot spots (if any) before hanging up.

<nelgin> Ah, here's a good one. If I ssh to my bbs server, then ssh to my bbs, do whatever then /O to logout, when I left click in the putty window I get "0;98;20M0;98;20m and stuff like that. I have to run reset to get it working properly.

src/sbbs3/main.cpp

@@ -3968,6 +3968,7 @@ int sbbs_t::mv(const char* path, const char* dest, bool copy)
 void sbbs_t::hangup(void)
 {
 	if(online) {
+		clear_hotspots();
 		lprintf(LOG_DEBUG,"disconnecting client");
 		online=FALSE;	// moved from the bottom of this function on Jan-25-2009
 	}