Convert more drivers for bsd-core, moving the ioctl definitions to shared

    code. Remove the "drv" from sisdrv, as it's unnecessary. Use the
    drm_pci functions in i915 instead of per-os implementations of the
    same. Avoid whitespace within fields in drm_pciids.txt (one of the r300
    definitions), since it breaks the bsd pciids script. Tested on sis,
    mga, r128. i915 needs more work.