Fix BrlAPI refresh on xbrlapi setfocus notification. (st)
Fix BrlAPI refresh on xbrlapi setfocus notification. (st)

Braille rendering was not flushed when xbrlapi notifies brltty of the
focus change. Also, we need to make sure to flush rendering when the
displayed connection changes - so far we were just lucky that the cursor
position was different and thus triggered a flush.

brltty/brltty,brltty/brltty,brltty/brltty,brltty/brltty,brltty/brltty,brltty/brltty