Use libcorkscrew for stack unwinding.

Change-Id: Iee1ee5a2018ab8cfc1ce12ec2a124809245eaa02
diff --git a/libs/utils/Android.mk b/libs/utils/Android.mk
index 831d9e3..d168d19 100644
--- a/libs/utils/Android.mk
+++ b/libs/utils/Android.mk
@@ -105,7 +105,8 @@
 	libz \
 	liblog \
 	libcutils \
-	libdl
+	libdl \
+	libcorkscrew
 
 LOCAL_MODULE:= libutils
 include $(BUILD_SHARED_LIBRARY)