Small fix for crashing log window when written from other thread

For some reason, changing this code to this makes it stop crashing when writing to the console from another thread.
The value from `_lines.Count` was not the same in `virtualListView1.VirtualListSize`, maybe write to VirtuListSize are delayed?

Author: Skarsnik

src/BizHawk.Client.EmuHawk/LogWindow.cs

@@ -103,7 +103,7 @@ private void append(string str, bool invoked)
 		private void doUpdateListSize()
 		{
 			virtualListView1.VirtualListSize = _lines.Count;
-			virtualListView1.EnsureVisible(_lines.Count - 1);
+			virtualListView1.EnsureVisible(virtualListView1.VirtualListSize - 1);
 		}
 
 		private void appendInvoked(string str)
@@ -218,3 +218,4 @@ public override void Write(char[] buffer, int offset, int count)
 		}
 	}
 }
+