post_proc: Audiosphere SA+ concurrency implementation

Audiosphere effect cannot be used along with any other SA+
effects, and needs handling for such concurrent use cases.
Add audiosphere controls to post_proc module, here both
audiosphere and SA+ events are made available providing
easy detection and handling for concurrent use cases.

Change-Id: Ifc2ac493442dda1fbe564b066fab0710a14d1759
diff --git a/post_proc/Android.mk b/post_proc/Android.mk
index 192320a..929991c 100644
--- a/post_proc/Android.mk
+++ b/post_proc/Android.mk
@@ -21,6 +21,11 @@
     LOCAL_SRC_FILES += hw_accelerator.c
 endif
 
+ifeq ($(strip $(AUDIO_FEATURE_ENABLED_AUDIOSPHERE)),true)
+    LOCAL_CFLAGS += -DAUDIOSPHERE_ENABLED
+    LOCAL_SRC_FILES += asphere.c
+endif
+
 LOCAL_CFLAGS+= -O2 -fvisibility=hidden
 
 ifneq ($(strip $(AUDIO_FEATURE_DISABLED_DTS_EAGLE)),true)