Add ED25519 as signature OID

Reviewed-by: NRich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/3503)

crypto/objects/obj_xref.h

@@ -73,6 +73,7 @@ static const nid_triple sigoid_srt[] = {
      NID_id_GostR3410_2012_256},
     {NID_id_tc26_signwithdigest_gost3410_2012_512, NID_id_GostR3411_2012_512,
      NID_id_GostR3410_2012_512},
+    {NID_ED25519, NID_undef, NID_ED25519},
 };
 
 static const nid_triple *const sigoid_srt_xref[] = {

crypto/objects/obj_xref.txt

@@ -17,6 +17,7 @@ ripemd160WithRSA	ripemd160 rsaEncryption
 # AlgorithmIdentifier. The digest "undef" indicates the public key
 # method should handle this explicitly.
 rsassaPss		undef	rsaEncryption
+ED25519		    undef	ED25519
 
 # Alternative deprecated OIDs. By using the older "rsa" OID this
 # type will be recognized by not normally used.