build system: clean up

CMakeLists.txt

@@ -206,4 +206,3 @@ set(
 )
 
 add_custom_target(aob SOURCES ${AOB_SOURCES})
-source_group(TREE "${CMAKE_CURRENT_SOURCE_DIR}" FILES ${AOB_SOURCES})

docs/CMakeLists.txt

@@ -37,5 +37,3 @@ install(
     DIRECTORY ${DOXY_OUTPUT_DIRECTORY}/html
     DESTINATION share/${PROJECT_NAME}-${PROJECT_VERSION}/
 )
-
-source_group(TREE "${CMAKE_CURRENT_SOURCE_DIR}" FILES ${DOC_SOURCES})