CMake fix to build cltool on Ubuntu 20.04

[andreucm]

On Ubuntu 20.04, with

$ uname -a
Linux maupas 5.15.0-107-generic #117~20.04.1-Ubuntu SMP Tue Apr 30 10:35:57 UTC 2024 x86_64 x86_64 x86_64 GNU/Linux

I have to fix this line on the CMakeLists file, replacing it by:

link_directories(${IS_SDK_DIR}/build)

Doing so , the cltool utility can be built successfully, otherwise the following linking error appears:

100%] Linking CXX executable cltool
/usr/bin/ld: cannot find -lInertialSenseSDK
collect2: error: ld returned 1 exit status
make[2]: *** [CMakeFiles/cltool.dir/build.make:99: cltool] Error 1
make[1]: *** [CMakeFiles/Makefile2:76: CMakeFiles/cltool.dir/all] Error 2
make: *** [Makefile:84: all] Error 2