Fix with libxml >=2.14

Index: src/utils/dumplibs.cpp
--- src/utils/dumplibs.cpp.orig
+++ src/utils/dumplibs.cpp
@@ -140,9 +140,8 @@ void dumpLibs()
     LIBXML_TEST_VERSION
 #endif  // LIBXML_TEST_VERSION
 #ifdef ENABLE_LIBXML
-    const char **xmlVersion = __xmlParserVersion();
-    if (xmlVersion != nullptr)
-        logger->log(" libxml2: %s", *xmlVersion);
+    const char *const xmlVersion = xmlParserVersion;
+    logger->log(" libxml2: %s", xmlVersion);
 #endif  // ENABLE_LIBXML
 #ifdef USE_SDL2
     SDL_version sdlVersion;
@@ -161,12 +160,9 @@ void dumpLibs()
 
     compareVersions("zLib", ZLIB_VERSION, zlibVersion());
 #ifdef ENABLE_LIBXML
-    if (xmlVersion != nullptr)
-    {
-        compareVersions("libxml2",
-            LIBXML_VERSION_STRING LIBXML_VERSION_EXTRA,
-            *xmlVersion);
-    }
+    compareVersions("libxml2",
+        LIBXML_VERSION_STRING LIBXML_VERSION_EXTRA,
+        xmlVersion);
 #endif  // ENABLE_LIBXML
 #ifdef USE_SDL2
     compareSDLVersions("SDL", sdlVersionJoin(SDL), &sdlVersion);
