asoc: codecs: Change TX tuning and reduce RX click and pop

Update TX requantizer gain coefficients to center
gain errors around zero. To reduce click and pop
on audio playback enable reference buffers of
headphone path in hifi mode and then put it to
the usecase specific power mode.

Change-Id: I0013d6258d5e5a8c92fd0f951d1d89e5906b2faf
Signed-off-by: Karthikeyan Mani <kmani@codeaurora.org>

asoc/codecs/wcd938x/internal.h

@@ -144,6 +144,7 @@ enum {
 	WCD_BOLERO_EVT_RX_MUTE = 1,	/* for RX mute/unmute */
 	WCD_BOLERO_EVT_IMPED_TRUE,	/* for imped true */
 	WCD_BOLERO_EVT_IMPED_FALSE,	/* for imped false */
+	WCD_BOLERO_EVT_RX_COMPANDER_SOFT_RST,
 };
 
 enum {