Remove useless Boost related lines in pcl.cmake

Removes Boost_USE_STATIC which does not exist in CMake > 3.0.
Removes Boost_LIBRARY_DIR_DEBUG/RELEASE which are automatically set by FindBoost.cmake according to BOOST_LIBRARYDIR hint.

Projects/pcl.cmake

@@ -8,11 +8,8 @@ superbuild_add_project(pcl
   -DBoost_NO_BOOST_CMAKE:BOOL=ON
   -DBoost_USE_MULTITHREAD:BOOL=ON
   -DBoost_USE_STATIC_LIBS:BOOL=OFF
-  -DBoost_USE_STATIC:BOOL=OFF
   -DPCL_BUILD_WITH_BOOST_DYNAMIC_LINKING_WIN32:BOOL=ON
   -DBOOST_LIBRARYDIR:PATH=<INSTALL_DIR>/lib
-  -DBoost_LIBRARY_DIR_DEBUG:PATH=<INSTALL_DIR>/lib
-  -DBoost_LIBRARY_DIR_RELEASE:PATH=<INSTALL_DIR>/lib
   -DEIGEN_INCLUDE_DIR=<INSTALL_DIR>/include/eigen3
   -DQHULL_LIBRARY:FILEPATH=<INSTALL_DIR>/lib/${CMAKE_STATIC_LIBRARY_PREFIX}qhullstatic${CMAKE_STATIC_LIBRARY_SUFFIX}
   -DQHULL_LIBRARY_DEBUG:FILEPATH=<INSTALL_DIR>/lib/${CMAKE_STATIC_LIBRARY_PREFIX}qhullstatic${CMAKE_STATIC_LIBRARY_SUFFIX}