[Foundation] _Bridged[Stored]NSError: Remove explicit impls for hashValue/_rawHashValue

The compiler-synthesized / stdlib-provided default implementations seem perfectly fine for these.

Author: lorentey

stdlib/public/Darwin/Foundation/NSError.swift

@@ -409,12 +409,6 @@ extension _BridgedNSError where Self.RawValue: FixedWidthInteger {
   public func hash(into hasher: inout Hasher) {
     hasher.combine(_code)
   }
-
-  public var hashValue: Int { return _code }
-
-  public func _rawHashValue(seed: Int) -> Int {
-    return _code._rawHashValue(seed: seed)
-  }
 }
 
 /// Describes a bridged error that stores the underlying NSError, so
@@ -492,14 +486,6 @@ extension _BridgedStoredNSError {
   public func hash(into hasher: inout Hasher) {
     hasher.combine(_nsError)
   }
-
-  public var hashValue: Int {
-    return _nsError.hash
-  }
-
-  public func _rawHashValue(seed: Int) -> Int {
-    return _nsError._rawHashValue(seed: seed)
-  }
 }
 
 /// Describes the code of an error.