s390: add missing declarations

arch_dup_task_struct and the per cpu variable mt_cycles are globally
visible, but do not have any header file with a declaration.
Therefore add it so we have proper type checking in place.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

arch/s390/include/asm/thread_info.h

@@ -62,6 +62,7 @@ static inline struct thread_info *current_thread_info(void)
 }
 
 void arch_release_task_struct(struct task_struct *tsk);
+int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src);
 
 #define THREAD_SIZE_ORDER THREAD_ORDER
 

arch/s390/kernel/entry.h

 #ifndef _ENTRY_H
 #define _ENTRY_H
 
+#include <linux/percpu.h>
 #include <linux/types.h>
 #include <linux/signal.h>
 #include <asm/ptrace.h>
@@ -75,4 +76,7 @@ long sys_s390_personality(unsigned int personality);
 long sys_s390_runtime_instr(int command, int signum);
 long sys_s390_pci_mmio_write(unsigned long, const void __user *, size_t);
 long sys_s390_pci_mmio_read(unsigned long, void __user *, size_t);
+
+DECLARE_PER_CPU(u64, mt_cycles[8]);
+
 #endif /* _ENTRY_H */

arch/s390/kernel/vtime.c

@@ -18,6 +18,8 @@
 #include <asm/cpu_mf.h>
 #include <asm/smp.h>
 
+#include "entry.h"
+
 static void virt_timer_expire(void);
 
 static LIST_HEAD(virt_timer_list);