mptcp: remove unused 'remaining' variable

In some functions, 'remaining' variable was given in argument and/or set
but never read.

  net/mptcp/options.c:779:3: warning: Value stored to 'remaining' is never
  read [clang-analyzer-deadcode.DeadStores].

  net/mptcp/options.c:547:3: warning: Value stored to 'remaining' is never
  read [clang-analyzer-deadcode.DeadStores].

The issue has been reported internally by Alibaba CI.
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Suggested-by: Mat Martineau <martineau@kernel.org>
Co-developed-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/mptcp/options.c

@@ -442,7 +442,6 @@ static void clear_3rdack_retransmission(struct sock *sk)
 static bool mptcp_established_options_mp(struct sock *sk, struct sk_buff *skb,
 					 bool snd_data_fin_enable,
 					 unsigned int *size,
-					 unsigned int remaining,
 					 struct mptcp_out_options *opts)
 {
 	struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk);
@@ -556,7 +555,6 @@ static void mptcp_write_data_fin(struct mptcp_subflow_context *subflow,
 static bool mptcp_established_options_dss(struct sock *sk, struct sk_buff *skb,
 					  bool snd_data_fin_enable,
 					  unsigned int *size,
-					  unsigned int remaining,
 					  struct mptcp_out_options *opts)
 {
 	struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk);
@@ -580,7 +578,6 @@ static bool mptcp_established_options_dss(struct sock *sk, struct sk_buff *skb,
 			opts->ext_copy = *mpext;
 		}
 
-		remaining -= map_size;
 		dss_size = map_size;
 		if (skb && snd_data_fin_enable)
 			mptcp_write_data_fin(subflow, skb, &opts->ext_copy);
@@ -851,9 +848,9 @@ bool mptcp_established_options(struct sock *sk, struct sk_buff *skb,
 	}
 
 	snd_data_fin = mptcp_data_fin_enabled(msk);
-	if (mptcp_established_options_mp(sk, skb, snd_data_fin, &opt_size, remaining, opts))
+	if (mptcp_established_options_mp(sk, skb, snd_data_fin, &opt_size, opts))
 		ret = true;
-	else if (mptcp_established_options_dss(sk, skb, snd_data_fin, &opt_size, remaining, opts)) {
+	else if (mptcp_established_options_dss(sk, skb, snd_data_fin, &opt_size, opts)) {
 		unsigned int mp_fail_size;
 
 		ret = true;