Support scrollwheel in offline scrollback.

src/syncterm/bbslist.c

@@ -290,6 +290,8 @@ void viewofflinescroll(void)
 	gotoxy(1,1);
 	textattr(uifc.hclr|(uifc.bclr<<4)|BLINK);
 	gettextinfo(&sbtxtinfo);
+	ciomouse_addevent(CIOLIB_BUTTON_4_PRESS);
+	ciomouse_addevent(CIOLIB_BUTTON_5_PRESS);
 
 	for(i=0;!i && !quitting;) {
 		if(top<1)
@@ -320,6 +322,12 @@ void viewofflinescroll(void)
 							case CIOLIB_BUTTON_1_DRAG_START:
 								mousedrag(scrollback_buf);
 								break;
+							case CIOLIB_BUTTON_4_PRESS:
+								top--;
+								break;
+							case CIOLIB_BUTTON_5_PRESS:
+								top++;
+								break;
 						}
 						break;
 					case CIO_KEY_UP: