nir/lower_tex: support for lowering RECT textures

v2: comments/suggestions from Ilia and Eric, split out get_texture_size()
helper so we can use it in the next commit for clamping RECT textures.

Signed-off-by: Rob Clark <robclark@freedesktop.org>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
2 files changed