Fix bazel benchmark build

tensorflow/lite/micro/BUILD

@@ -110,6 +110,7 @@ cc_library(
         "//tensorflow/lite/core/api",
         "//tensorflow/lite/kernels:op_macros",
         "//tensorflow/lite/kernels/internal:compatibility",
+        "//tensorflow/lite/micro/kernels:ethosu",
         "//tensorflow/lite/micro/kernels:fully_connected",
         "//tensorflow/lite/micro/kernels:micro_ops",
         "//tensorflow/lite/schema:schema_fbs",

tensorflow/lite/micro/benchmarks/BUILD

@@ -41,6 +41,7 @@ cc_binary(
         "//tensorflow/lite/micro:micro_error_reporter",
         "//tensorflow/lite/micro:micro_framework",
         "//tensorflow/lite/micro:op_resolvers",
+        "//tensorflow/lite/micro/kernels:ethosu",
         "//tensorflow/lite/micro/kernels:fully_connected",
     ],
 )

tensorflow/lite/micro/kernels/BUILD

@@ -95,6 +95,26 @@ cc_library(
     }),
 )
 
+cc_library(
+    name = "ethosu",
+    srcs = select({
+        "//conditions:default": [
+            "ethosu.cc",
+        ],
+    }),
+    hdrs = ["ethosu.h"],
+    copts = micro_copts(),
+    visibility = [
+        # Kernel variants need to be visible to the examples and benchmarks.
+        ":micro",
+    ],
+    deps = [
+        "//tensorflow/lite/c:common",
+    ] + select({
+        "//conditions:default": [],
+    }),
+)
+
 cc_library(
     name = "micro_ops",
     srcs = [