net/ncsi: Make local function ncsi_get_filter() static

Fixes the following sparse warnings:

net/ncsi/ncsi-manage.c:41:5: warning:
 symbol 'ncsi_get_filter' was not declared. Should it be static?
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ncsi/ncsi-manage.c

@@ -38,7 +38,7 @@ static inline int ncsi_filter_size(int table)
 	return sizes[table];
 }
 
-u32 *ncsi_get_filter(struct ncsi_channel *nc, int table, int index)
+static u32 *ncsi_get_filter(struct ncsi_channel *nc, int table, int index)
 {
 	struct ncsi_channel_filter *ncf;
 	int size;