Use VESA palette load/save functions if VESA BIOS says the current palette format is higher than 6-bit instead of relying VGA compatibility flag. This fixes palette problem of NVIDIA GeForce 6600.  Reduce code differences between palette load/save functions while we are here.
Use VESA palette load/save functions if VESA BIOS says the current palette
format is higher than 6-bit instead of relying VGA compatibility flag.
This fixes palette problem of NVIDIA GeForce 6600.  Reduce code differences
between palette load/save functions while we are here.

Tested by:	danfe

jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase