glsl_to_tgsi: allocate glsl_to_tgsi_instruction::tex_offsets on demand

sizeof(glsl_to_tgsi_instruction): 384 -> 264

Reviewed-by: Ilia Mirkin <imirkin@alum.mit.edu>
Reviewed-by: Nicolai Hähnle <nicolai.haehnle@amd.com>
1 file changed