[MIPS] MIPS MT: Fix build error.

Signed-off-by: Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/kernel/mips-mt.c

@@ -7,6 +7,7 @@
 #include <linux/sched.h>
 #include <linux/cpumask.h>
 #include <linux/interrupt.h>
+#include <linux/security.h>
 
 #include <asm/cpu.h>
 #include <asm/processor.h>