nir/lower_tex: handle query lod with nir_lower_tex_packing_16 at lower_tex_packing
packing_16 with floats assumed 1 (shadow) or 4 components. But query lod operations return 2.
Fixes the following test with v3dv: dEQP-VK.ycbcr.query.lod.fragment.r8g8b8a8_unorm