nir: make nir_const_value scalar

v2: remove & operator in a couple of memsets
    add some memsets
v3: fixup lima

Signed-off-by: Karol Herbst <kherbst@redhat.com>
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net> (v2)
diff --git a/src/gallium/drivers/panfrost/midgard/midgard_compile.c b/src/gallium/drivers/panfrost/midgard/midgard_compile.c
index dada2bf..203e6cd 100644
--- a/src/gallium/drivers/panfrost/midgard/midgard_compile.c
+++ b/src/gallium/drivers/panfrost/midgard/midgard_compile.c
@@ -865,7 +865,7 @@
         nir_ssa_def def = instr->def;
 
         float *v = ralloc_array(NULL, float, 4);
-        memcpy(v, &instr->value.f32, 4 * sizeof(float));
+        nir_const_load_to_arr(v, instr, f32);
         _mesa_hash_table_u64_insert(ctx->ssa_constants, def.index + 1, v);
 }