tcp: cleanup ca_state mess in tcp_timer

Redundant checks made indentation impossible to follow.
However, it might be useful to make this ca_state+is_sack
indexed array.
Signed-off-by: NIlpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/ipv4/tcp_timer.c

@@ -328,19 +328,16 @@ static void tcp_retransmit_timer(struct sock *sk)
 	if (icsk->icsk_retransmits == 0) {
 		int mib_idx;
 
-		if (icsk->icsk_ca_state == TCP_CA_Disorder ||
-		    icsk->icsk_ca_state == TCP_CA_Recovery) {
-			if (tcp_is_sack(tp)) {
-				if (icsk->icsk_ca_state == TCP_CA_Recovery)
-					mib_idx = LINUX_MIB_TCPSACKRECOVERYFAIL;
-				else
-					mib_idx = LINUX_MIB_TCPSACKFAILURES;
-			} else {
-				if (icsk->icsk_ca_state == TCP_CA_Recovery)
-					mib_idx = LINUX_MIB_TCPRENORECOVERYFAIL;
-				else
-					mib_idx = LINUX_MIB_TCPRENOFAILURES;
-			}
+		if (icsk->icsk_ca_state == TCP_CA_Disorder) {
+			if (tcp_is_sack(tp))
+				mib_idx = LINUX_MIB_TCPSACKFAILURES;
+			else
+				mib_idx = LINUX_MIB_TCPRENOFAILURES;
+		} else if (icsk->icsk_ca_state == TCP_CA_Recovery) {
+			if (tcp_is_sack(tp))
+				mib_idx = LINUX_MIB_TCPSACKRECOVERYFAIL;
+			else
+				mib_idx = LINUX_MIB_TCPRENORECOVERYFAIL;
 		} else if (icsk->icsk_ca_state == TCP_CA_Loss) {
 			mib_idx = LINUX_MIB_TCPLOSSFAILURES;
 		} else {