bpfilter: Fix mismatch in function argument types

Fix following warning:
net/ipv4/bpfilter/sockopt.c:28:5: error: symbol 'bpfilter_ip_set_sockopt' redeclared with different type
net/ipv4/bpfilter/sockopt.c:34:5: error: symbol 'bpfilter_ip_get_sockopt' redeclared with different type

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/linux/bpfilter.h

@@ -5,10 +5,10 @@
 #include <uapi/linux/bpfilter.h>
 
 struct sock;
-int bpfilter_ip_set_sockopt(struct sock *sk, int optname, char *optval,
+int bpfilter_ip_set_sockopt(struct sock *sk, int optname, char __user *optval,
 			    unsigned int optlen);
-int bpfilter_ip_get_sockopt(struct sock *sk, int optname, char *optval,
-			    int *optlen);
+int bpfilter_ip_get_sockopt(struct sock *sk, int optname, char __user *optval,
+			    int __user *optlen);
 extern int (*bpfilter_process_sockopt)(struct sock *sk, int optname,
 				       char __user *optval,
 				       unsigned int optlen, bool is_set);