Blackfin arch: add asm/thread_info.h for THREAD_SIZE define

Signed-off-by: Mike Frysinger <vapier.adi@gmail.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>

diff --git a/arch/blackfin/mach-common/head.S b/arch/blackfin/mach-common/head.S
index 8514da5..6a989a0 100644
--- a/arch/blackfin/mach-common/head.S
+++ b/arch/blackfin/mach-common/head.S
@@ -11,6 +11,7 @@
 #include <linux/linkage.h>
 #include <linux/init.h>
 #include <asm/blackfin.h>
+#include <asm/thread_info.h>
 #include <asm/trace.h>
 
 /* A little BF561 glue ... */