Fixed an issue with freeing memory when reading string markers from L…

…SL (e.g., for online BCI). Not sure why this happens, but it seems we're using the wrong allocator to free the LSL memory (currently leaking a small amt of mem, need to fix at some point).

dependencies/liblsl-Matlab/mex/build-DESKTOP-CD7CPRK/env_add.m

@@ -0,0 +1 @@
+any(cellfun(@exist,{'lsl_pull_sample_str'})==3)

dependencies/liblsl-Matlab/mex/lsl_pull_sample_str.c

@@ -62,7 +62,7 @@ void mexFunction( int nlhs, mxArray *plhs[],
         /* move data over into the results */
         for (k=0;k<numchannels;k++) {
             mxSetCell(plhs[0],k,mxCreateString(buffer[k]));
-            free(buffer[k]);
+            /* free(buffer[k]); -- leak memory so we don't crash... */
         }
         if (nlhs == 2) {
             /* also assign the time stamp */