sysctl: Make do_sysctl static

Now that all of the architectures use compat_sys_sysctl do_sysctl
can become static.
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>

include/linux/sysctl.h

@@ -996,10 +996,6 @@ extern int proc_doulongvec_minmax(struct ctl_table *, int,
 extern int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int,
 				      void __user *, size_t *, loff_t *);
 
-extern int do_sysctl (int __user *name, int nlen,
-		      void __user *oldval, size_t __user *oldlenp,
-		      void __user *newval, size_t newlen);
-
 extern ctl_handler sysctl_data;
 extern ctl_handler sysctl_string;
 extern ctl_handler sysctl_intvec;

kernel/sysctl_binary.c

@@ -135,7 +135,7 @@ static void deprecated_sysctl_warning(const int *name, int nlen)
 	return;
 }
 
-int do_sysctl(int __user *args_name, int nlen,
+static int do_sysctl(int __user *args_name, int nlen,
 	void __user *oldval, size_t __user *oldlenp,
 	void __user *newval, size_t newlen)
 {