copy-paste include directory fix for static library too

CMakeLists.txt

@@ -113,6 +113,11 @@ target_include_directories(HexEx
         $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/src>
         $<INSTALL_INTERFACE:${CMAKE_INSTALL_INCLUDEDIR}>
         )
+target_include_directories(HexExStatic
+        INTERFACE
+        $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/src>
+        $<INSTALL_INTERFACE:${CMAKE_INSTALL_INCLUDEDIR}>
+        )
 
 set_target_properties (HexExStatic
     PROPERTIES