[CMake] drop pkg-config

CMakeLists.txt

-# Copyright 2018, Gepetto team, LAAS-CNRS
+# Copyright 2018, 2021, Gepetto team, LAAS-CNRS
 #
 
 CMAKE_MINIMUM_REQUIRED(VERSION 3.1)
@@ -49,12 +49,11 @@ IF(BUILD_PYTHON_INTERFACE)
   SEARCH_FOR_BOOST_PYTHON(REQUIRED)
   STRING(REGEX REPLACE "-" "_" PROJECT_NAME_UNDERSCORE ${PROJECT_NAME})
   SET(PY_NAME ${PROJECT_NAME_UNDERSCORE})
-  ADD_PROJECT_DEPENDENCY(dynamic-graph-python 4.0.0 REQUIRED
-    PKG_CONFIG_REQUIRES dynamic-graph-python)
+  ADD_PROJECT_DEPENDENCY(dynamic-graph-python 4.0.0 REQUIRED)
 ENDIF(BUILD_PYTHON_INTERFACE)
 
-ADD_PROJECT_DEPENDENCY(sot-core REQUIRED PKG_CONFIG_REQUIRES sot-core)
-ADD_PROJECT_DEPENDENCY(eiquadprog REQUIRED PKG_CONFIG_REQUIRES eiquadprog)
+ADD_PROJECT_DEPENDENCY(sot-core REQUIRED)
+ADD_PROJECT_DEPENDENCY(eiquadprog REQUIRED)
 ADD_PROJECT_DEPENDENCY(parametric-curves REQUIRED)
 
 # Verbosity level
@@ -107,7 +106,6 @@ IF(BUILD_TESTING)
   ADD_SUBDIRECTORY(tests)
 ENDIF(BUILD_TESTING)
 
-PKG_CONFIG_APPEND_LIBS(${PROJECT_NAME})
 IF(NOT INSTALL_PYTHON_INTERFACE_ONLY)
   INSTALL(FILES package.xml DESTINATION share/${PROJECT_NAME})
 ENDIF(NOT INSTALL_PYTHON_INTERFACE_ONLY)