[CMake] fix eigen include dir for Fedora

CMakeLists.txt

@@ -83,7 +83,7 @@ SET(${PROJECT_NAME}_HEADERS
   )
 
 ADD_LIBRARY(${PROJECT_NAME} INTERFACE)
-TARGET_INCLUDE_DIRECTORIES(${PROJECT_NAME} SYSTEM INTERFACE ${EIGEN3_INCLUDE_DIRS})
+TARGET_INCLUDE_DIRECTORIES(${PROJECT_NAME} SYSTEM INTERFACE ${EIGEN3_INCLUDE_DIR})
 TARGET_INCLUDE_DIRECTORIES(${PROJECT_NAME} INTERFACE $<INSTALL_INTERFACE:include>)
 IF(CURVES_WITH_PINOCCHIO_SUPPORT)
   TARGET_LINK_LIBRARIES(${PROJECT_NAME} INTERFACE pinocchio::pinocchio)