audio: Initial support for amplifier HALs

Change-Id: I04ef5b89ca595a0df02f6a4a68748bd0d0cdb245
(cherry picked from commit 7a82a0e691d884045c78d1cb9f7ab0dd51a5d871)
diff --git a/audio/Android.mk b/audio/Android.mk
index 9ececd2..3d9b14a 100644
--- a/audio/Android.mk
+++ b/audio/Android.mk
@@ -32,6 +32,7 @@
 	liblog \
 	libcutils \
 	libaudioutils \
+	libhardware \
 	libtinyalsa \
 	libtinycompress \
 	libaudioroute \
@@ -43,6 +44,7 @@
 	$(LOCAL_PATH)/include \
 	external/tinyalsa/include \
 	external/tinycompress/include \
+	hardware/libhardware/include \
 	hardware/samsung/ril/libsecril-client \
 	$(call include-path-for, audio-utils) \
 	$(call include-path-for, audio-route) \