add FilePermission deprecations

Author: rauhul

Sources/System/FileStatus/FileMode/FilePermissions.swift

@@ -118,12 +118,14 @@ public struct FilePermissions: OptionSet, Hashable, Codable {
   ///
   /// For more information, see the `setuid(2)` man page.
   @_alwaysEmitIntoClient
+  @available(*, deprecated, renamed: "FileModeOther.setUserID")
   public static var setUserID: FilePermissions { FilePermissions(0o4000) }
 
   /// Indicates that the file is executed as the group.
   ///
   /// For more information, see the `setgid(2)` man page.
   @_alwaysEmitIntoClient
+  @available(*, deprecated, renamed: "FileModeOther.setGroupID")
   public static var setGroupID: FilePermissions { FilePermissions(0o2000) }
 
   /// Indicates that executable's text segment
@@ -132,6 +134,7 @@ public struct FilePermissions: OptionSet, Hashable, Codable {
   /// For more information, see the `chmod(2)` man page's
   /// discussion of `S_ISVTX` (the sticky bit).
   @_alwaysEmitIntoClient
+  @available(*, deprecated, renamed: "FileModeOther.saveText")
   public static var saveText: FilePermissions { FilePermissions(0o1000) }
 }