MediaCodecListOverrides_test: Remove compile_multilib

MediaCodecListOverrides_test can be built for both 64 and 32 bit
configurations.

Also remove libstagefright_omx and omx includes that aren't needed.

Bug: 178228919
Test: atest MediaCodecListOverrides_test
Change-Id: I895537457adfa0db62bf42a65ec70598ce4dd61e
diff --git a/media/libstagefright/tests/Android.bp b/media/libstagefright/tests/Android.bp
index 5f3f72c..4a505d4 100644
--- a/media/libstagefright/tests/Android.bp
+++ b/media/libstagefright/tests/Android.bp
@@ -9,7 +9,6 @@
         "libmedia",
         "libstagefright",
         "libstagefright_foundation",
-        "libstagefright_omx",
         "libutils",
         "liblog",
     ],
@@ -17,11 +16,8 @@
     include_dirs: [
         "frameworks/av/media/libstagefright",
         "frameworks/av/media/libstagefright/include",
-        "frameworks/native/include/media/openmax",
     ],
 
-    compile_multilib: "prefer32",
-
     cflags: [
         "-Werror",
         "-Wall",