Use -Werror in hardware/qcom/audio

* Suppress existing warnings.

Bug: 66996870
Test: build with WITH_TIDY=1
Change-Id: I389b943471ccdcfc9b7db4411fa3973d77303a27
diff --git a/post_proc/Android.mk b/post_proc/Android.mk
index 493f2cc..54dcc77 100644
--- a/post_proc/Android.mk
+++ b/post_proc/Android.mk
@@ -2,6 +2,12 @@
 
 LOCAL_PATH:= $(call my-dir)
 
+qcom_post_proc_common_cflags := \
+    -O2 -fvisibility=hidden \
+    -Wall -Werror \
+    -Wno-unused-function \
+    -Wno-unused-variable \
+
 include $(CLEAR_VARS)
 
 LOCAL_SRC_FILES:= \
@@ -12,7 +18,7 @@
 	reverb.c \
 	effect_api.c
 
-LOCAL_CFLAGS+= -O2 -fvisibility=hidden
+LOCAL_CFLAGS += $(qcom_post_proc_common_cflags)
 
 LOCAL_SHARED_LIBRARIES := \
 	libcutils \
@@ -44,7 +50,7 @@
 LOCAL_SRC_FILES:= \
 	volume_listener.c
 
-LOCAL_CFLAGS+= -O2 -fvisibility=hidden
+LOCAL_CFLAGS += $(qcom_post_proc_common_cflags)
 
 LOCAL_SHARED_LIBRARIES := \
 	libcutils \
diff --git a/visualizer/Android.mk b/visualizer/Android.mk
index e318214..4b73704 100644
--- a/visualizer/Android.mk
+++ b/visualizer/Android.mk
@@ -21,6 +21,11 @@
 
 LOCAL_CFLAGS+= -O2 -fvisibility=hidden
 
+LOCAL_CFLAGS+= \
+    -Wall \
+    -Werror \
+    -Wno-unused-variable \
+
 LOCAL_SHARED_LIBRARIES := \
 	libcutils \
 	liblog \
diff --git a/voice_processing/Android.mk b/voice_processing/Android.mk
index e8878ee..ffe0330 100644
--- a/voice_processing/Android.mk
+++ b/voice_processing/Android.mk
@@ -12,6 +12,12 @@
 LOCAL_SRC_FILES:= \
     voice_processing.c
 
+LOCAL_CFLAGS += \
+    -Wall \
+    -Werror \
+    -Wno-unused-function \
+    -Wno-unused-variable \
+
 LOCAL_C_INCLUDES += \
     $(call include-path-for, audio-effects)