std.EnumSet: add back deprecated initialization functions

lib/std/enums.zig

@@ -284,6 +284,18 @@ pub fn EnumSet(comptime E: type) type {
         /// A set containing all possible keys.
         pub const full: Self = .{ .bits = .full };
 
+        /// Deprecated: use `.empty`.
+        /// Returns a set containing no keys.
+        pub fn initEmpty() Self {
+            return .empty;
+        }
+
+        /// Deprecated: use `.full`.
+        /// Returns a set containing all possible keys.
+        pub fn initFull() Self {
+            return .full;
+        }
+
         /// Returns a set containing multiple keys.
         pub fn initMany(keys: []const Key) Self {
             var set: Self = .empty;