m32r: build fix for removing fs.h from mm.h

This patch fixes the m32r build after the commit "Remove fs.h from mm.h"
was merged (commit 4e950f6f0189f65f8bf069cf2272649ef418f5e4).

Signed-off-by: Hirokazu Takata <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

arch/m32r/kernel/ptrace.c

···
 #include <linux/kernel.h>
 #include <linux/sched.h>
 #include <linux/mm.h>
+#include <linux/err.h>
 #include <linux/smp.h>
 #include <linux/smp_lock.h>
 #include <linux/errno.h>

arch/m32r/kernel/smpboot.c

···
 #include <linux/init.h>
 #include <linux/kernel.h>
 #include <linux/mm.h>
+#include <linux/err.h>
 #include <linux/irq.h>
 #include <linux/bootmem.h>
 #include <linux/delay.h>

arch/m32r/kernel/sys_m32r.c

···
 #include <linux/errno.h>
 #include <linux/sched.h>
 #include <linux/mm.h>
+#include <linux/fs.h>
 #include <linux/smp.h>
 #include <linux/sem.h>
 #include <linux/msg.h>