Make qiconvcodec work correctly in DragonFly BSD

It would be nice if qiconvcodec would work correctly in DragonFly BSD system.
DragonFly BSD has Citrus iconv (http://citrus.bsdclub.org) implementation in the base system.

The following patch was offered as a solution for this which seeks to handle Citrus iconv versions 1.13
— src/corelib/codecs/qiconvcodec.cpp.orig 2008-04-28 16:11:18 +0300
+++ src/corelib/codecs/qiconvcodec.cpp 2008-05-08 10:14:05 +0300
@@ -50,9 +50,14 @@
#include <stdio.h>
#include <dlfcn.h>

+// for __DragonFly_version
+#if defined(_DragonFly_)
+#include <sys/param.h>
+#endif
+
// unistd.h is needed for the _XOPEN_UNIX macro
#include <unistd.h>
-#if defined(_XOPEN_UNIX) && !defined(Q_OS_QNX6) && !defined(Q_OS_OSF)
+#if (defined(XOPEN_UNIX) && !defined(Q_OS_QNX6) && !defined(Q_OS_OSF)) || defined(DragonFly_)

1. include <langinfo.h>
   #endif

@@ -69,6 +74,9 @@

1. else
2. define UTF16 "UTF-16LE"
3. endif
   +#elif defined(_DragonFly_) && __DragonFly_version < 197700
   +# define NO_BOM
   +# define UTF16 "UTF-16"
   #else
4. define UTF16 "UTF-16"
   #endif
   @@ -296,7 +304,7 @@
   char *codeset = 0;
   #endif

-#if defined(_XOPEN_UNIX) && !defined(Q_OS_QNX6) && !defined(Q_OS_OSF)
+#if (defined(XOPEN_UNIX) && !defined(Q_OS_QNX6) && !defined(Q_OS_OSF)) || defined(DragonFly_)
if (cd == (iconv_t) -1) {
codeset = nl_langinfo(CODESET);
if (codeset)