Exclude some unavailable errors from NSError.

OpenBSD doesn't support these particular errno symbols. Exclude them for
this platform.

Author: 3405691582

Sources/Foundation/NSError.swift

@@ -1344,6 +1344,7 @@ extension POSIXError {
     /// Bad message.
     public static var EBADMSG: POSIXError.Code { return .EBADMSG }
 
+    #if !os(OpenBSD)
     /// Reserved.
     public static var EMULTIHOP: POSIXError.Code { return .EMULTIHOP }
 
@@ -1358,13 +1359,16 @@ extension POSIXError {
 
     /// Not a STREAM.
     public static var ENOSTR: POSIXError.Code { return .ENOSTR }
+    #endif
 
     /// Protocol error.
     public static var EPROTO: POSIXError.Code { return .EPROTO }
 
+    #if !os(OpenBSD)
     /// STREAM ioctl timeout.
     public static var ETIME: POSIXError.Code { return .ETIME }
     #endif
+    #endif
 
     #if canImport(Darwin)
     /// No such policy registered.