srsRAN-matlab: breaking change

[dvdgrgrtt]

Hi!
Just a quick note to inform you that we have changed our approach to the MEX libraries in our companion testing repository srsRAN-matlab.

Before: The MEX libraries were built directly into the +srsMEX folder, where the rest of the MATLAB code would search for them.

Now: The MEX libraries are built into their specific directory within the CMake build tree, and then they need to be explicitly installed into the +srsMEX folder.

Why: The new approach makes things easier for those of us that work with different versions of the MEX libraries (different compilation flags, different MATLAB versions, ...) since we can now easily switch from one pre-compiled version to another by simply running cmake --install builddirX, where builddirX is the CMake build folder of MEX version X. With the old approach, switching versions required a clean (i.e., from scratch) built of the MEX libraries.

For more information, please refer to the MEX section of the srsRAN-matlab README file.