Didn't build on FreeBSD because it does not define SOL_TCP

Replaced SOL_TCP with getprotobyname("TCP")->p_proto

BUG: 324766

kded/devicelinks/landevicelink.cpp

@@ -23,6 +23,7 @@
 #include <sys/socket.h>
 #include <netinet/in.h>
 #include <netinet/tcp.h>
+#include <netdb.h>
 
 #include "linkproviders/linkprovider.h"
 #include "networkpackage.h"
@@ -40,10 +41,10 @@ LanDeviceLink::LanDeviceLink(const QString& d, LinkProvider* a, QTcpSocket* sock
     setsockopt(fd, IPPROTO_TCP, TCP_KEEPIDLE, &maxIdle, sizeof(maxIdle));
 
     int count = 3;  // send up to 3 keepalive packets out, then disconnect if no response
-    setsockopt(fd, SOL_TCP, TCP_KEEPCNT, &count, sizeof(count));
+    setsockopt(fd, getprotobyname("TCP")->p_proto, TCP_KEEPCNT, &count, sizeof(count));
 
     int interval = 5;   // send a keepalive packet out every 2 seconds (after the 5 second idle period)
-    setsockopt(fd, SOL_TCP, TCP_KEEPINTVL, &interval, sizeof(interval));
+    setsockopt(fd, getprotobyname("TCP")->p_proto, TCP_KEEPINTVL, &interval, sizeof(interval));
 
     connect(mSocket, SIGNAL(disconnected()),
             this, SLOT(deleteLater()));