forked from Imagelibrary/rtems
1. Finally fixes raw interrupts for pc386
2. Makes some minor cleanup in console and startup
3. Makes rtems_termios_dequeue_characters() to return count of
outstanding chars - it allows to simplify console isrs a little
bit.
4. pc386 uart modified to be friendlier to termios parameter changes,
to have minor performance improvement and to take advantage of
of above termios modification.