audio: hal: Add support for registering adsp events

Add support for AHAL clients to register for adsp events
and receive event callbacks when an event is triggered by adsp.

CRs-Fixed: 2023812
Change-Id: Ie22efee6e859c3d819ed3939e164cb7baebab71b
diff --git a/hal/Android.mk b/hal/Android.mk
index 5dbada0..9a8d27c 100644
--- a/hal/Android.mk
+++ b/hal/Android.mk
@@ -346,6 +346,11 @@
     LOCAL_SRC_FILES += audio_extn/gef.c
 endif
 
+ifeq ($(strip $($AUDIO_FEATURE_ADSP_HDLR_ENABLED)),true)
+    LOCAL_CFLAGS += -DAUDIO_EXTN_ADSP_HDLR_ENABLED
+    LOCAL_SRC_FILES += audio_extn/adsp_hdlr.c
+endif
+
 LOCAL_CFLAGS += -Wall -Werror
 
 LOCAL_COPY_HEADERS_TO   := mm-audio