Forgot to update the CMakeLists.txt in doc folder

doc/CMakeLists.txt

@@ -3,9 +3,9 @@ find_package(Doxygen)
 IF(NOT DOXYGEN_FOUND)
     MESSAGE(STATUS "No Doxygen found. Documentation won't be built")
 ELSE()
-    file(GLOB SOURCES ${CMAKE_SOURCE_DIR}/include/*)
-    file(GLOB MARKDOWN_DOC ${CMAKE_SOURCE_DIR}/doc/*.md)
-    list(APPEND MARKDOWN_DOC ${CMAKE_SOURCE_DIR}/readme.md)
+    file(GLOB SOURCES ${CMAKE_CURRENT_LIST_DIR}/../include/*)
+    file(GLOB MARKDOWN_DOC ${CMAKE_CURRENT_LIST_DIR}/../doc/*.md)
+    list(APPEND MARKDOWN_DOC ${CMAKE_CURRENT_LIST_DIR}/../readme.md)
 
     CONFIGURE_FILE(Doxyfile.in Doxyfile @ONLY)
     CONFIGURE_FILE(Doxyfile.zh-cn.in Doxyfile.zh-cn @ONLY)
@@ -15,7 +15,7 @@ ELSE()
         COMMAND ${DOXYGEN_EXECUTABLE} ${CMAKE_CURRENT_BINARY_DIR}/Doxyfile.zh-cn
         COMMAND ${CMAKE_COMMAND} -E touch ${CMAKE_CURRENT_BINARY_DIR}/html
         DEPENDS ${MARKDOWN_DOC} ${SOURCES} ${CMAKE_CURRENT_BINARY_DIR}/Doxyfile*
-        WORKING_DIRECTORY ${CMAKE_SOURCE_DIR}
+        WORKING_DIRECTORY ${CMAKE_CURRENT_LIST_DIR}/../
         )
 
     add_custom_target(doc ALL DEPENDS html)