case, software cursor now optional case. Driver must provide
raw things (what hardware do for us, exactly) as default case,
all driver features must be _optional_. Modern VGAs have internal
configuration utilities to set cursor shape/blinking which stored
into cards ROM, and syscons nuke out such features completely
by forcing software cursor. Moreover, software cursor is hard
to distinguish on standouted (or near standouted) fields and
tends to disappearse from the screen.
Set "flags 0x4" to enable software cursor now.
o Cleanup screen savers.
o Don't draw cursor if saver or blinker is active.
o Duplicated code moved to functons.
o Add more checks for blinker in progress, character lost otherwise
when blinker restore old contents.
o Reduce blinking counter to 3, too slow in old variant.
o Fix timeout code in scrn_timer(), old variant can reenter iself,
if action takes too long time.
o Disable visual bell for scroll lock mode, saved screen
becomes overwritted otherwise.