i965: Parameterize HiZ code to prepare for adding blitting.

i965: Parameterize HiZ code to prepare for adding blitting.

This patch groups together the parameters used by the HiZ functions
into a new data structure, brw_hiz_resolve_params, rather than passing
each parameter individually between the HiZ functions.  This data
structure is a subclass of brw_blorp_params, which represents the
parameters of a general-purpose blit or resolve operation.  A future
patch will add another subclass for blits.

In addition, this patch generalizes the (width, height) parameters to
a full rect (x0, y0, x1, y1), since blitting operations will need to
be able to operate on arbitrary rectangles.  Also, it renames several
of the HiZ functions to reflect the expanded role they will serve.

v2: Rename brw_hiz_resolve_params to brw_hiz_op_params.  Move
gen{6,7}_blorp_exec() functions back into gen{6,7}_blorp.h.

Reviewed-by: Chad Versace <chad.versace@linux.intel.com>