- VBE 3.0 says palette format resets to 6-bit mode when video mode changes.
We simply set 8-bit mode when we switch modes if the adapter supports it.
- VBE 3.0 also says if the mode is not VGA compatible, we must use VBE
function to save/restore palette. Otherwise, VGA function may be used.
Thus, reinstate the save/load palette functions only for non-VGA compatible
modes regardless of its palette format.
- Let vesa(4) set VESA modes even if vga(4) claims to support it.
- Reset default palette if VESA pixel mode is set initially.
- Fix more style nits.