std.mem: delete workaround now that zig1.wasm is updated

lib/std/mem.zig

@@ -636,18 +636,14 @@ test lessThan {
     try testing.expect(lessThan(u8, "", "a"));
 }
 
-/// Normally, we could simply use `builtin.fuzz` but this requires a zig1.wasm
-/// update. After the next zig1.wasm update, the `@hasDecl` can be removed.
-const fuzz = @hasDecl(builtin, "fuzz") and builtin.fuzz;
-
 const eqlBytes_allowed = switch (builtin.zig_backend) {
     // The SPIR-V backend does not support the optimized path yet.
     .stage2_spirv64 => false,
     // The RISC-V does not support vectors.
     .stage2_riscv64 => false,
     // The naive memory comparison implementation is more useful for fuzzers to
     // find interesting inputs.
-    else => !fuzz,
+    else => !builtin.fuzz,
 };
 
 /// Compares two slices and returns whether they are equal.