Makefile: split compilation and linkage
This fixes an error when compiling with clang++:
clang: error: cannot specify -o when generating multiple output files
<builtin>: recipe for target 'opencv_trail_effect' failed
make: *** [opencv_trail_effect] Error 1
The error happens because in this Makefile header files are in the
target dependencies, so they are added to the compilation command, but
clang does not support that when compiling and linking in the same
command.
Also take care of using LIKN.cpp to link the program, as it is a C++
program.