librealsense: Building process of Intel Realsense Legacy v1.12.1 library stops with errors

Issue Description

Hi, I have tried to build the library in my Linux Mint distribution and it was not possible because the #include <functional> was not included in librealsense/src/types.h. After adding #include <functional> to .../librealsense/src/types.h, the building process was resumed but halted again showing the errors below. From the messages it seems to be again a library is missing… am I right or am I doing something wrong?

/home/xxx/Software/librealsense/src/uvc-v4l2.cpp: In constructor ‘rsimpl::uvc::subdevice::subdevice(const string&)’:
/home/xxx/Software/librealsense/src/uvc-v4l2.cpp:109:66: error: ‘major’ was not declared in this scope
  109 |                 std::ostringstream ss; ss << "/sys/dev/char/" << major(st.st_rdev) << ":" << minor(st.st_rdev) << "/device/";
      |                                                                  ^~~~~
/home/xxx/Software/librealsense/src/uvc-v4l2.cpp:109:94: error: ‘minor’ was not declared in this scope; did you mean ‘mincore’?
  109 |                 std::ostringstream ss; ss << "/sys/dev/char/" << major(st.st_rdev) << ":" << minor(st.st_rdev) << "/device/";
      |                                                                                              ^~~~~
      |                                                                                              mincore
make[2]: *** [CMakeFiles/realsense.dir/build.make:323: CMakeFiles/realsense.dir/src/uvc-v4l2.cpp.o] Error 1
make[1]: *** [CMakeFiles/Makefile2:189: CMakeFiles/realsense.dir/all] Error 2
make: *** [Makefile:130: all] Error 2