configs: Enable custom stereo flag for APQ8009

Enable custom stereo flag to support multichannel
to mono conversion.

CRs-Fixed: 2273661
Change-Id: Ic8b4bbe1ab7cee9a7370fa6cadc8ccf35c1c9559
diff --git a/configs/msm8909/msm8909.mk b/configs/msm8909/msm8909.mk
index 15d08c1..be16a96 100644
--- a/configs/msm8909/msm8909.mk
+++ b/configs/msm8909/msm8909.mk
@@ -44,6 +44,7 @@
 BOARD_SUPPORTS_QSTHW_API := true
 AUDIO_FEATURE_DISABLED_SOUND_TRIGGER_LEGACY_HAL := true
 AUDIO_FEATURE_ENABLED_COMPRESS_INPUT := true
+AUDIO_FEATURE_ENABLED_CUSTOMSTEREO := true
 
 ##AUDIO_FEATURE_FLAGS