find_package(IPCL) does not work without installation

[WeiDaiWD]

Assuming cmake -S . -B build ..., without installation, find_package(IPCL HINTS ${IPCL}/cmake/ipcl-2.0.0) can find cmake/ipcl-2.0.0/IPCLConfig.cmake. Then IPCLConfig.cmake points to non-existing IPCLConfigVersion.cmake and IPCLTargets.cmake files that are instead generated to build/ipcl/cmake/ipcl-2.0.0/.

Replacing IPCL_ROOT_DIR on this line by CMAKE_CURRENT_BINARY_DIR should fix the issue.