cmake: pyside2: use imported targets if available

src/Gui/CMakeLists.txt

@@ -180,9 +180,15 @@ if(SHIBOKEN_INCLUDE_DIR)
     include_directories(
         ${SHIBOKEN_INCLUDE_DIR}
     )
-    list(APPEND FreeCADGui_LIBS
-        ${SHIBOKEN_LIBRARY}
-    )
+    if (TARGET Shiboken2::libshiboken)
+        list(APPEND FreeCADGui_LIBS
+            Shiboken2::libshiboken
+        )
+    else(TARGET Shiboken2::libshiboken)
+        list(APPEND FreeCADGui_LIBS
+            ${SHIBOKEN_LIBRARY}
+        )
+    endif(TARGET Shiboken2::libshiboken)
 endif(SHIBOKEN_INCLUDE_DIR)
 
 if(PYSIDE_INCLUDE_DIR)
@@ -191,9 +197,15 @@ if(PYSIDE_INCLUDE_DIR)
         ${PYSIDE_INCLUDE_DIR}/QtCore
         ${PYSIDE_INCLUDE_DIR}/QtGui
     )
-    list(APPEND FreeCADGui_LIBS
-        ${PYSIDE_LIBRARY}
-    )
+    if (TARGET PySide2::pyside2)
+        list(APPEND FreeCADGui_LIBS
+            PySide2::pyside2
+        )
+    else(TARGET PySide2::pyside2)
+        list(APPEND FreeCADGui_LIBS
+            ${PYSIDE_LIBRARY}
+        )
+    endif(TARGET PySide2::pyside2)
     if (BUILD_QT5)
         include_directories(
             ${PYSIDE_INCLUDE_DIR}/QtWidgets