radv: Call nir_propagate_invariant()

Without this, invariant qualifiers don't do anything. Together with a
fix to the game, this fixes flickering in No Man's Sky.

Cc: mesa-stable@lists.freedesktop.org
Reviewed-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
diff --git a/src/amd/vulkan/radv_shader.c b/src/amd/vulkan/radv_shader.c
index 729aaba..1ab64a6 100644
--- a/src/amd/vulkan/radv_shader.c
+++ b/src/amd/vulkan/radv_shader.c
@@ -389,6 +389,8 @@
 		NIR_PASS_V(nir, nir_remove_dead_variables,
 		           nir_var_shader_in | nir_var_shader_out | nir_var_system_value);
 
+		NIR_PASS_V(nir, nir_propagate_invariant);
+
 		NIR_PASS_V(nir, nir_lower_system_values);
 		NIR_PASS_V(nir, nir_lower_clip_cull_distance_arrays);
 		NIR_PASS_V(nir, radv_nir_lower_ycbcr_textures, layout);