hal: Support for FLAC 24 bit format in offload path

- Add flac in supported codecs list
- Set FLAC codec specific parameters
- Set fragment size based on bit width and sampling rate
  for flac.
- Configure backend to 24/16 bit based on the current
  usecases running

Change-Id: If013078e277fd3053fba6489345803f8f58bd86d
diff --git a/hal/audio_hw.h b/hal/audio_hw.h
index 6b2f999..622f9ac 100644
--- a/hal/audio_hw.h
+++ b/hal/audio_hw.h
@@ -183,6 +183,7 @@
     void *offload_cookie;
     struct compr_gapless_mdata gapless_mdata;
     int send_new_metadata;
+    unsigned int bit_width;
 
     struct audio_device *dev;
 };
@@ -256,6 +257,8 @@
     unsigned int cur_wfd_channels;
 
     int snd_card;
+    unsigned int cur_codec_backend_samplerate;
+    unsigned int cur_codec_backend_bit_width;
     void *platform;
     unsigned int offload_usecases_state;
     void *visualizer_lib;