Fix comment on AUDIO_FORMAT_PCM_SUB_8_24_BIT

Should be Q8.23 (24 bits packed in the least significant
3 bytes).

Change-Id: If5ca27c27249487e28c0be42ebdd283308ff8552
diff --git a/include/system/audio.h b/include/system/audio.h
index c8efdf3..17bf260 100644
--- a/include/system/audio.h
+++ b/include/system/audio.h
@@ -194,7 +194,7 @@
     AUDIO_FORMAT_PCM_SUB_16_BIT          = 0x1, /* DO NOT CHANGE - PCM signed 16 bits */
     AUDIO_FORMAT_PCM_SUB_8_BIT           = 0x2, /* DO NOT CHANGE - PCM unsigned 8 bits */
     AUDIO_FORMAT_PCM_SUB_32_BIT          = 0x3, /* PCM signed .31 fixed point */
-    AUDIO_FORMAT_PCM_SUB_8_24_BIT        = 0x4, /* PCM signed 7.24 fixed point */
+    AUDIO_FORMAT_PCM_SUB_8_24_BIT        = 0x4, /* PCM signed 8.23 fixed point */
     AUDIO_FORMAT_PCM_SUB_FLOAT           = 0x5, /* PCM single-precision floating point */
     AUDIO_FORMAT_PCM_SUB_24_BIT_PACKED   = 0x6, /* PCM signed .23 fixed point packed in 3 bytes */
 } audio_format_pcm_sub_fmt_t;