[AVR32] Implement stacktrace support

Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
diff --git a/arch/avr32/kernel/Makefile b/arch/avr32/kernel/Makefile
index 989fcd1..2d6d48f3 100644
--- a/arch/avr32/kernel/Makefile
+++ b/arch/avr32/kernel/Makefile
@@ -11,3 +11,4 @@
 obj-y				+= init_task.o switch_to.o cpu.o
 obj-$(CONFIG_MODULES)		+= module.o avr32_ksyms.o
 obj-$(CONFIG_KPROBES)		+= kprobes.o
+obj-$(CONFIG_STACKTRACE)	+= stacktrace.o