make State::new() const, consistent with others

embassy-stm32/src/eth/v2/mod.rs

@@ -19,7 +19,7 @@ use super::*;
 
 pub struct State<'d, T: Instance, const TX: usize, const RX: usize>(StateStorage<Inner<'d, T, TX, RX>>);
 impl<'d, T: Instance, const TX: usize, const RX: usize> State<'d, T, TX, RX> {
-    pub fn new() -> Self {
+    pub const fn new() -> Self {
         Self(StateStorage::new())
     }
 }