[PATCH net-next] tipc: remove set but not used variable 'prev'

[YueHaibing]

Fixes gcc '-Wunused-but-set-variable' warning:

net/tipc/msg.c: In function 'tipc_msg_append':
net/tipc/msg.c:215:24: warning:
 variable 'prev' set but not used [-Wunused-but-set-variable]

commit 0a3e060f340d ("tipc: add test for Nagle algorithm effectiveness")
left behind this, remove it.

Signed-off-by: YueHaibing <yuehaib...@huawei.com>
---
 net/tipc/msg.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/net/tipc/msg.c b/net/tipc/msg.c
index 23809039dda1..c0afcd627c5e 100644
--- a/net/tipc/msg.c
+++ b/net/tipc/msg.c
@@ -212,7 +212,7 @@ int tipc_buf_append(struct sk_buff **headbuf, struct 
sk_buff **buf)
 int tipc_msg_append(struct tipc_msg *_hdr, struct msghdr *m, int dlen,
                    int mss, struct sk_buff_head *txq)
 {
-       struct sk_buff *skb, *prev;
+       struct sk_buff *skb;
        int accounted, total, curr;
        int mlen, cpy, rem = dlen;
        struct tipc_msg *hdr;
@@ -223,7 +223,6 @@ int tipc_msg_append(struct tipc_msg *_hdr, struct msghdr 
*m, int dlen,
 
        while (rem) {
                if (!skb || skb->len >= mss) {
-                       prev = skb;
                        skb = tipc_buf_acquire(mss, GFP_KERNEL);
                        if (unlikely(!skb))
                                return -ENOMEM;