audio: Add ACDB INIT extension

- Add an audio extension for ACDB
- ACDB Init from AHAL and STHAL are routed via this extension

CRs-Fixed: 2028493
Change-Id: Ib63c8fa4bf1f89d4dbfce8b6584ac1d8271e5f38
diff --git a/hal/Makefile.am b/hal/Makefile.am
index cbce291..0edf504 100644
--- a/hal/Makefile.am
+++ b/hal/Makefile.am
@@ -11,7 +11,8 @@
             platform_info.c \
             ${TARGET_PLATFORM}/platform.c \
             audio_extn/audio_extn.c \
-            audio_extn/utils.c
+            audio_extn/utils.c \
+            acdb.c
 
 if HDMI_EDID
 AM_CFLAGS += -DHDMI_EDID