i965: Update SF, SBE, and RASTER state for Broadwell.

i965: Update SF, SBE, and RASTER state for Broadwell.

The attribute override portion of 3DSTATE_SBE was split out into
3DSTATE_SBE_SWIZ; various bits of 3DSTATE_SF were split out into
3DSTATE_RASTER.

v2: Set Force URB Read Offset bit.  Eventually the URB read offset
    should be set in 3DSTATE_VS, but that will require some refactoring.

v3: Rebase on viewport array changes.

v4: Improve comments about URB read length/offset overrides.

Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Eric Anholt <eric@anholt.net>