Fix wav test on Apple toolchain (#15506)

Summary:

As titled.

Reviewed By: GregoryComer

Differential Revision: D85998220

Author: larryliu0820

extension/llm/runner/test/targets.bzl

@@ -3,7 +3,11 @@
 #
 # This source code is licensed under the BSD-style license found in the
 # LICENSE file in the root directory of this source tree.
-
+load(
+    "@fbsource//tools/build_defs:default_platform_defs.bzl",
+    "ANDROID",
+    "CXX",
+)
 load("@fbsource//xplat/executorch/build:runtime_wrapper.bzl", "runtime")
 
 def define_common_targets():
@@ -63,4 +67,5 @@ def define_common_targets():
             "//executorch/extension/llm/runner:multimodal_runner_lib",
             "//executorch/runtime/platform:platform",
         ],
+        platforms = [CXX, ANDROID],
     )

extension/llm/runner/test/test_wav_loader.cpp

@@ -258,11 +258,10 @@ TEST_F(WavLoaderTest, LoadAudioDataRejectsUnsupportedFormat) {
   const std::vector<uint8_t> wav_bytes =
       make_wav_bytes_with_format(0x0006, 16, sample_data);
   TempFile file(wav_bytes.data(), wav_bytes.size());
-
 #if ET_LOG_ENABLED
   EXPECT_DEATH(
       { load_wav_audio_data(file.path()); }, "Unsupported audio format");
 #else
   EXPECT_DEATH({ load_wav_audio_data(file.path()); }, "");
-#endif
+#endif // ET_LOG_ENABLED
 }