nir: add names to function parameters

SPIR-V has this information. We should try to preserve it.

Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Reviewed-by: Marek Olšák <marek.olsak@amd.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/32208>

src/compiler/nir/nir.h

@@ -3650,6 +3650,9 @@ typedef struct {
 
    /* The type of the function param */
    const struct glsl_type *type;
+
+   /* Name if known, null if unknown */
+   const char *name;
 } nir_parameter;
 
 typedef struct nir_function {