configs: kona: Add flag to compile opensource sthal

The sound trigger hal is moving from proprietary to opensource on
kona. This flag will enable compilation of the code in the
opensource location and disable compilation of the code in the
proprietary location.

Change-Id: I527524d8055c1a2f00e33640dfbef6b09fd53c08
diff --git a/configs/kona/kona.mk b/configs/kona/kona.mk
index c091ce6..ed56ff3 100644
--- a/configs/kona/kona.mk
+++ b/configs/kona/kona.mk
@@ -81,6 +81,9 @@
 AUDIO_FEATURE_ENABLED_BATTERY_LISTENER := true
 ##AUDIO_FEATURE_FLAGS
 
+#Compile opensource sthal and disable compiling of proprietary sthal
+BOARD_SUPPORTS_OPENSOURCE_STHAL := true
+
 AUDIO_HARDWARE := audio.a2dp.default
 AUDIO_HARDWARE += audio.usb.default
 AUDIO_HARDWARE += audio.r_submix.default