rusticl: fix clippy lint having bounds defined in multiple places

Fixes: 734352ddfb ("rusticl/program: some boilerplate code for SPIR-V support")
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/30410>

src/gallium/frontends/rusticl/api/util.rs

@@ -224,9 +224,9 @@ where
     }
 }
 
-pub fn cl_prop<T: CLProp>(v: T) -> Vec<MaybeUninit<u8>>
+pub fn cl_prop<T>(v: T) -> Vec<MaybeUninit<u8>>
 where
-    T: Sized,
+    T: CLProp + Sized,
 {
     v.cl_vec()
 }