The ARR codepath used if ctx->target_version >= NV2 does not account for
the correction offset, but the indirect addressing reads do, which
ultimately results in incorrect offsets. Since the limitation goes away
as soon as we enable GL_NV_vertex_program_2_option ignoring the offset
is the best thing to do. I don't set shader_data->rel_offset to zero in
the pre-compilation analysis because enablding NV_vertex_program2 is in
theory a decision that is taken later during code generation.