fix serde compile bug

src/x25519.rs

@@ -25,6 +25,7 @@ use rand_core::CryptoRng;
 
 /// A `PublicKey` is the corresponding public key converted from
 /// an `EphemeralSecret` or a `StaticSecret` key.
+#[cfg_attr(feature = "serde", serde(crate = "our_serde"))]
 #[cfg_attr(feature = "serde", derive(our_serde::Serialize, our_serde::Deserialize))]
 #[derive(Copy, Clone, Debug)]
 pub struct PublicKey(pub (crate) MontgomeryPoint);
@@ -89,6 +90,7 @@ impl<'a> From<&'a EphemeralSecret> for PublicKey {
 /// their `PublicKey`.
 // FIXME: serialize and deserialize derived methods will not work
 // because x25519 requires non-canonical scalars which are rejected by curve25519-dalek
+#[cfg_attr(feature = "serde", serde(crate = "our_serde"))]
 #[cfg_attr(feature = "serde", derive(our_serde::Serialize, our_serde::Deserialize))]
 #[derive(Clone)]
 pub struct StaticSecret(pub (crate) Scalar);