soundwire: change the max bra data size per frame value

According to mipi SoundWire DisCo Specification_v2-1, this maximum
value shall not exceed 470.

Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>

Author: bardliao

include/linux/soundwire/sdw.h

@@ -835,11 +835,10 @@ struct sdw_defer {
 };
 
 /*
- * Add a practical limit to BPT transfer sizes. BPT is typically used
- * to transfer firmware, and larger firmware transfers will increase
- * the cold latency beyond typical OS or user requirements.
+ * According to mipi SoundWire DisCo Specification_v2-1,
+ * this maximum value shall not exceed 470.
  */
-#define SDW_BPT_MSG_MAX_BYTES  (1024 * 1024)
+#define SDW_BPT_MSG_MAX_BYTES  470
 
 struct sdw_bpt_msg;