Update audio_bytes_per_sample for PCM 24 bit packed

Change-Id: Ic79f604893f5c4f2e8e35189d6638b5b160435ed
Signed-off-by: Andy Hung <hunga@google.com>
diff --git a/include/system/audio.h b/include/system/audio.h
index 294139d..35639b5 100644
--- a/include/system/audio.h
+++ b/include/system/audio.h
@@ -633,6 +633,9 @@
     case AUDIO_FORMAT_PCM_8_24_BIT:
         size = sizeof(int32_t);
         break;
+    case AUDIO_FORMAT_PCM_24_BIT_PACKED:
+        size = sizeof(uint8_t) * 3;
+        break;
     case AUDIO_FORMAT_PCM_16_BIT:
         size = sizeof(int16_t);
         break;