i965: Delete fast copy blit code

i965: Delete fast copy blit code

Fast copy blit was primarily added to support Yf/Ys detiling.
But, Yf/Ys tiling never got used in i965 due to not delivering
the expected performance benefits. Also, replacing legacy blits
with fast copy blit didn't help the benchmarking numbers. This
is probably due to a h/w restriction that says "start pixel for
Fast Copy blit should be on an OWord boundary". This restriction
causes many blit operations to skip fast copy blit and use legacy
blits. So, this patch is deleting this dead code in favor of
adding it later when we actually find it useful.

Signed-off-by: Anuj Phogat <anuj.phogat@gmail.com>
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>