Suppress implicit-fallthrough warnings in libaudioclient.

Add FALLTHROUGH_INTENDED for clang compiler.

Bug: 112564944
Test: build with global -Wimplicit-fallthrough.
Change-Id: Icafaff606364fe7bffaad1e9c2e763c444ea999c
diff --git a/media/libaudioclient/Android.bp b/media/libaudioclient/Android.bp
index 2df37a8..f93d44b 100644
--- a/media/libaudioclient/Android.bp
+++ b/media/libaudioclient/Android.bp
@@ -53,7 +53,10 @@
     export_shared_lib_headers: ["libbinder"],
 
     local_include_dirs: ["include/media", "aidl"],
-    header_libs: ["libaudioclient_headers"],
+    header_libs: [
+        "libaudioclient_headers",
+        "libbase_headers",
+    ],
     export_header_lib_headers: ["libaudioclient_headers"],
 
     // for memory heap analysis