anv/lower_input_attachments: honor sample index parameter to subpassLoad()
According to GL_KHR_vulkan_glsl, the signature of subpassLoad() is:
gvec4 subpassLoad(gsubpassInput subpass);
gvec4 subpassLoad(gsubpassInputMS subpass, int sample);
So the multisampled case always receives an explicit sample index that we
should use. The current implementation was ignoring this parameter
and using gl_SampleID value instead.
Fixes:
dEQP-VK.pipeline.multisample_shader_builtin.sample_id.*
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Cc: "17.0" <mesa-stable@lists.freedesktop.org>
(cherry picked from commit
9b25769da63999fa65a70a14194a452c49d18f3e)