i965: Update 3DSTATE_PS, 3DSTATE_WM, and add 3DSTATE_PS_EXTRA.

i965: Update 3DSTATE_PS, 3DSTATE_WM, and add 3DSTATE_PS_EXTRA.

v2: Fix setting of GEN8_PSX_ATTRIBUTE_ENABLE after rebases.

v3: Add missing binding table entry counts.  Don't worry about alpha
    testing or alpha to coverage when setting the "Kill Pixel" bit;
    those are specified in 3DSTATE_PS_BLEND (caught by Eric Anholt).
    Drop unused _NEW_BUFFERS.  Tidy comments.

v4: Rebase on Paul Berry's changes to CurrentFragmentProgram.

v5: Re-enable line stippling.  It doesn't crash or anything.

Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Eric Anholt <eric@anholt.net> [v3]