i965/miptree: Rename align_w,align_h -> halign,valign

i965/miptree: Rename align_w,align_h -> halign,valign

The values of intel_mipmap_tree::align_w and ::align_h correspond to the
hardware enums HALIGN_* and VALIGN_*.

See the confusion?
    align_h != HALIGN
    align_h == VALIGN

Reduce the confusion by renaming the variables to match the hardware
enum names:
    git ls-files |
    xargs sed -i -e 's/align_w/halign/g' \
                 -e 's/align_h/valign/g'

Suggested-by: Kenneth Graunke <kenneth@whitecape.org>
Acked-by: Ben Widawsky <benjamin.widawsky@intel.com>
Reviewed-by: Anuj Phogat <anuj.phogat@gmail.com>