Optional SoftMax benchmarks vs DNNL

PiperOrigin-RevId: 299494008
diff --git a/build_defs.bzl b/build_defs.bzl
index 9112ab2..7909811 100644
--- a/build_defs.bzl
+++ b/build_defs.bzl
@@ -38,6 +38,10 @@
     """Compiler flags to optionally enable ARM ComputeLibrary benchmarks."""
     return []
 
+def xnnpack_optional_dnnl_copts():
+    """Compiler flags to optionally enable Intel DNNL benchmarks."""
+    return []
+
 def xnnpack_optional_ruy_deps():
     """Optional Ruy dependencies."""
     return []
@@ -54,6 +58,10 @@
     """Optional ARM ComputeLibrary dependencies."""
     return []
 
+def xnnpack_optional_dnnl_deps():
+    """Optional Intel DNNL dependencies."""
+    return []
+
 def xnnpack_cc_library(
         name,
         srcs = [],