Toolbox: Disable unused-XXX warnings

For build-system CFLAGS clean-up, disable warnings locally.

Should be reverted when the code is fixed.

Bug: 18632512
Change-Id: Ia373784ec36d37545a7e50db1df9f8cc37d7bf30
diff --git a/toolbox/Android.mk b/toolbox/Android.mk
index 6fdf610..7d396e4 100644
--- a/toolbox/Android.mk
+++ b/toolbox/Android.mk
@@ -7,6 +7,10 @@
     -I$(LOCAL_PATH)/upstream-netbsd/include/ \
     -include bsd-compatibility.h \
 
+# Temporary, remove after cleanup. b/18632512
+common_cflags += -Wno-unused-variable \
+                 -Wno-unused-but-set-variable
+
 
 include $(CLEAR_VARS)
 LOCAL_SRC_FILES := upstream-netbsd/bin/cat/cat.c