Add VTS tests for audio effects

Added tests covering IEffect, IEqualizerEffect, and
ILoudnessEnhancer interfaces.

Minor corrections in the interface definitions and implementations:

 - fixed descriptions and @callflow annotations in IEffect;

 - fixed type used for band levels in IEqualizerEffect;

 - fixed specification of frequencies in IEqualizerEffect;

 - fixed some bugs in previously non-execrices Effects code;

 - warning messages changed to error messages.

Test: this is a test
Bug: 32022706
Change-Id: I0e0bc111b07d944ad8a0321e8b1ec703f8d1a73e
diff --git a/audio/effect/2.0/vts/functional/Android.bp b/audio/effect/2.0/vts/functional/Android.bp
index 1bc3f39..8a370cd 100644
--- a/audio/effect/2.0/vts/functional/Android.bp
+++ b/audio/effect/2.0/vts/functional/Android.bp
@@ -26,7 +26,10 @@
         "libhidltransport",
         "libnativehelper",
         "libutils",
+        "android.hardware.audio.common@2.0",
         "android.hardware.audio.effect@2.0",
+        "android.hidl.allocator@1.0",
+        "android.hidl.memory@1.0",
     ],
     static_libs: ["VtsHalHidlTargetTestBase"],
     cflags: [