Avoid matching on &Foo, when a plain Foo pattern works

The extra & in a pattern (match arm or if let) is unnecessary and only
makes the code harder to read. In most places it's enough to just
remove the & from the pattern, but in a few places a dereference (*)
needs to be added where the value captured in the pattern is used, as
removing the & changes the type of the captured value to be a
reference.

Overall, the changes are almost mechanical. Although the diff is huge,
it should be easy to read.

The clippy lint match_ref_pats warns about this. See:
https://rust-lang.github.io/rust-clippy/master/index.html#match_ref_pats

1 files changed, 16 insertions, 16 deletions

diff --git a/openpgp/src/types/mod.rs b/openpgp/src/types/mod.rs
index deec8203..cdad569f 100644
--- a/openpgp/src/types/mod.rs
+++ b/openpgp/src/types/mod.rs
@@ -426,14 +426,14 @@ impl Curve {
     /// ```
     pub fn oid(&self) -> &[u8] {
         match self {
-            &Curve::NistP256 => NIST_P256_OID,
-            &Curve::NistP384 => NIST_P384_OID,
-            &Curve::NistP521 => NIST_P521_OID,
-            &Curve::BrainpoolP256 => BRAINPOOL_P256_OID,
-            &Curve::BrainpoolP512 => BRAINPOOL_P512_OID,
-            &Curve::Ed25519 => ED25519_OID,
-            &Curve::Cv25519 => CV25519_OID,
-            &Curve::Unknown(ref oid) => oid,
+            Curve::NistP256 => NIST_P256_OID,
+            Curve::NistP384 => NIST_P384_OID,
+            Curve::NistP521 => NIST_P521_OID,
+            Curve::BrainpoolP256 => BRAINPOOL_P256_OID,
+            Curve::BrainpoolP512 => BRAINPOOL_P512_OID,
+            Curve::Ed25519 => ED25519_OID,
+            Curve::Cv25519 => CV25519_OID,
+            Curve::Unknown(ref oid) => oid,
         }
     }
 
@@ -457,14 +457,14 @@ impl Curve {
     /// supported.
     pub fn len(&self) -> Result<usize> {
         match self {
-            &Curve::NistP256 => Ok(256),
-            &Curve::NistP384 => Ok(384),
-            &Curve::NistP521 => Ok(521),
-            &Curve::BrainpoolP256 => Ok(256),
-            &Curve::BrainpoolP512 => Ok(512),
-            &Curve::Ed25519 => Ok(256),
-            &Curve::Cv25519 => Ok(256),
-            &Curve::Unknown(_) =>
+            Curve::NistP256 => Ok(256),
+            Curve::NistP384 => Ok(384),
+            Curve::NistP521 => Ok(521),
+            Curve::BrainpoolP256 => Ok(256),
+            Curve::BrainpoolP512 => Ok(512),
+            Curve::Ed25519 => Ok(256),
+            Curve::Cv25519 => Ok(256),
+            Curve::Unknown(_) =>
                 Err(Error::UnsupportedEllipticCurve(self.clone())
                     .into()),
         }