cmake: fix search path for urdfdom libraries when CMAKE_INSTALL_LIBDIR is not lib/
cmake: fix search path for urdfdom libraries when CMAKE_INSTALL_LIBDIR is not lib/

shadow-robot/urdfdom,robotology-dependencies/urdfdom,robotology-dependencies/urdfdom,keulYSMB/urdfdom,keulYSMB/urdfdom,shadow-robot/urdfdom,shadow-robot/urdfdom,keulYSMB/urdfdom,shadow-robot/urdfdom,keulYSMB/urdfdom,robotology-dependencies/urdfdom,robotology-dependencies/urdfdom