audio: hal: Fix to use correct EC_REF_RX

In 8610, we need to use I2S_RX as ec_ref_rx
parameter and for SLIM based targets use
SLIM_RX.

CRs-Fixed: 575647
Change-Id: Ia220498f302a58dc3dbd42b1874fa01f081ce3dd
diff --git a/hal/msm8974/platform.h b/hal/msm8974/platform.h
index 8518c7d..8356cab 100644
--- a/hal/msm8974/platform.h
+++ b/hal/msm8974/platform.h
@@ -183,8 +183,10 @@
 
 #ifdef PLATFORM_MSM8610
 #define LOWLATENCY_PCM_DEVICE 12
+#define EC_REF_RX "I2S_RX"
 #else
 #define LOWLATENCY_PCM_DEVICE 15
+#define EC_REF_RX "SLIM_RX"
 #endif
 #ifdef PLATFORM_MSM8x26
 #define COMPRESS_CAPTURE_DEVICE 20