hal: Add support for native-DSD and native sampling rates

 -set passthrough flag and diable gapless for native dsd
 -Select new backend for native dsd.
 -Add support for e2e playback of clips with sampling rate
  multiple of 44.1.

Change-Id: I6aa0ef5ea176a0923b0b88924ab046f9a11b7b12
diff --git a/hal/platform_api.h b/hal/platform_api.h
index 0bb73f3..60e46f1 100644
--- a/hal/platform_api.h
+++ b/hal/platform_api.h
@@ -27,6 +27,7 @@
 enum {
     NATIVE_AUDIO_MODE_SRC = 1,
     NATIVE_AUDIO_MODE_TRUE_44_1,
+    NATIVE_AUDIO_MODE_MULTIPLE_44_1,
     NATIVE_AUDIO_MODE_INVALID
 };
 
@@ -151,4 +152,6 @@
                           bool enable,
                           char * str);
 bool platform_supports_true_32bit();
+bool platform_check_codec_dsd_support(void *platform);
+int platform_get_backend_index(snd_device_t snd_device);
 #endif // AUDIO_PLATFORM_API_H