Tentatively unobsolete enum types

Author: rzikm

src/libraries/System.Net.Primitives/ref/System.Net.Primitives.cs

@@ -526,7 +526,6 @@ protected SocketException(System.Runtime.Serialization.SerializationInfo seriali
 }
 namespace System.Security.Authentication
 {
-    [Obsolete("KeyExchangeAlgorithm, KeyExchangeStrength, CipherAlgorithm, CipherAlgorithmStrength, HashAlgorithm and HashStrength properties of SslStream are obsolete. Use NegotiatedCipherSuite instead.", DiagnosticId = "SYSLIB0058", UrlFormat = "https://aka.ms/dotnet-warnings/{0}")]
     public enum CipherAlgorithmType
     {
         None = 0,
@@ -540,15 +539,13 @@ public enum CipherAlgorithmType
         Aes = 26129,
         Rc4 = 26625,
     }
-    [Obsolete("KeyExchangeAlgorithm, KeyExchangeStrength, CipherAlgorithm, CipherAlgorithmStrength, HashAlgorithm and HashStrength properties of SslStream are obsolete. Use NegotiatedCipherSuite instead.", DiagnosticId = "SYSLIB0058", UrlFormat = "https://aka.ms/dotnet-warnings/{0}")]
     public enum ExchangeAlgorithmType
     {
         None = 0,
         RsaSign = 9216,
         RsaKeyX = 41984,
         DiffieHellman = 43522,
     }
-    [Obsolete("KeyExchangeAlgorithm, KeyExchangeStrength, CipherAlgorithm, CipherAlgorithmStrength, HashAlgorithm and HashStrength properties of SslStream are obsolete. Use NegotiatedCipherSuite instead.", DiagnosticId = "SYSLIB0058", UrlFormat = "https://aka.ms/dotnet-warnings/{0}")]
     public enum HashAlgorithmType
     {
         None = 0,

src/libraries/System.Net.Primitives/src/System/Net/SecureProtocols/SslEnumTypes.cs

@@ -25,7 +25,6 @@ public enum SslProtocols
         Default = Ssl3 | Tls
     }
 
-    [Obsolete(Obsoletions.TlsCipherAlgorithmEnumsMessage, DiagnosticId = Obsoletions.TlsCipherAlgorithmEnumsDiagId, UrlFormat = Obsoletions.SharedUrlFormat)]
     public enum ExchangeAlgorithmType
     {
         None = 0,
@@ -34,7 +33,6 @@ public enum ExchangeAlgorithmType
         DiffieHellman = (Interop.Crypt32.ALG_CLASS_KEY_EXCHANGE | Interop.Crypt32.ALG_TYPE_DH | Interop.Crypt32.ALG_SID_DH_EPHEM),
     }
 
-    [Obsolete(Obsoletions.TlsCipherAlgorithmEnumsMessage, DiagnosticId = Obsoletions.TlsCipherAlgorithmEnumsDiagId, UrlFormat = Obsoletions.SharedUrlFormat)]
     public enum CipherAlgorithmType
     {
         None = 0,  // No encryption
@@ -49,7 +47,6 @@ public enum CipherAlgorithmType
         Null = (Interop.Crypt32.ALG_CLASS_ENCRYPT),  // 0-bit NULL cipher algorithm
     }
 
-    [Obsolete(Obsoletions.TlsCipherAlgorithmEnumsMessage, DiagnosticId = Obsoletions.TlsCipherAlgorithmEnumsDiagId, UrlFormat = Obsoletions.SharedUrlFormat)]
     public enum HashAlgorithmType
     {
         None = 0,