nir: add common convert_ycbcr for vulkan csc

Copied from anv, replaced state with passing model/range directly.

Signed-off-by: Jonathan Marek <jonathan@marek.ca>
Reviewed-by: Bas Nieuwenhuizen <bas@basnieuwenhuizen.nl>
Acked-by: Jason Ekstrand <jason@jlekstrand.net>
Reviewed-by: D Scott Phillips <d.scott.phillips@intel.com>
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4528>

src/compiler/nir/nir_vulkan.h

@@ -0,0 +1,12 @@
+/* SPDX-License-Identifier: MIT */
+
+#include "nir.h"
+#include "nir_builder.h"
+#include "vulkan/vulkan_core.h"
+
+nir_ssa_def *
+nir_convert_ycbcr_to_rgb(nir_builder *b,
+                         VkSamplerYcbcrModelConversion model,
+                         VkSamplerYcbcrRange range,
+                         nir_ssa_def *raw_channels,
+                         uint32_t *bpcs);