We initially just copied on v3dv, just in case we needed to modify
it. One year later the code is exactly the same, so let's move it to
common.

This fix an additional issue, as we were not using NEON when building
v3d_tiling.c for v3dv.

v2:
   * Add "#include util/u_box.h" at v3d_tiling.h, so we can't avoid
     the need to include it on other places. (Juan and Iago)

Reviewed-by: Iago Toral Quiroga <itoral@igalia.com>
Part-of: <!11121>