Do not build tqassistantclient for native tqt build

Embed static qassistantclient library for qt3 build
(cherry picked from commit b67c2e559a)

qtinterface/CMakeLists.txt

@@ -199,10 +199,31 @@ tde_add_library( tqt SHARED
 ##### tqassistantclient (shared) ##############################
 
 
-tde_add_library( tqassistantclient SHARED
-  SOURCES
-    tqassistantclient.cpp
-  VERSION 4.2.0
-  LINK ${QT_LIBRARIES} -lqassistantclient
-  DESTINATION ${LIB_INSTALL_DIR}
-)
+  find_library( QASSISTANTCLIENT_STATIC libqassistantclient.a )
+
+  if ( QASSISTANTCLIENT_STATIC )
+
+    add_library(qassistantclient STATIC IMPORTED)
+    set_property(TARGET qassistantclient PROPERTY
+                 IMPORTED_LOCATION ${QASSISTANTCLIENT_STATIC})
+
+    tde_add_library( tqassistantclient SHARED
+      SOURCES
+        tqassistantclient.cpp
+      VERSION 4.2.0
+      LINK ${QT_LIBRARIES}
+      EMBED qassistantclient
+      DESTINATION ${LIB_INSTALL_DIR}
+    )
+
+  else ( QASSISTANTCLIENT_STATIC )
+
+    tde_add_library( tqassistantclient SHARED
+      SOURCES
+        tqassistantclient.cpp
+      VERSION 4.2.0
+      LINK ${QT_LIBRARIES} -lqassistantclient
+      DESTINATION ${LIB_INSTALL_DIR}
+    )
+
+  endif ( QASSISTANTCLIENT_STATIC )