* add cursor on/off functions.
* Default cursor state is off (for framebuffer console).
* Turn off cursor in each driver's xxxCursorInit() entrypoint.
* Turn on cursor at the end of each driver's xxxLoadCursor() entrypoint.
works with X11R5 servers shipped with NetBSD 1.3.
Where CACHED_TO_HYS() is still needed for kernel-virtual-to-physical
or physical-to-uncached mapping (fb drivers), replace with
`#include <mips/cpuregs.h>'.
1. Start at the specified entry instead of entry 0.
2. Use the blue value instead of the green when setting the blue color entry.
3. Don't use the starting index again for storing the saved entry - the cmap
pointer was previously initialized using the starting index. This fixes
a hard hang on the maxine when console output is done after calls to
set the color map (usually by the X server).