`gkregex.c` has to include <strings.h> [over here](https://github.com/KarypisLab/GKlib/blob/master/gkregex.c#L92) on linux for the `strcasecmp` to be resolved. Related to [SU2/2409](https://github.com/su2code/SU2/issues/2409).
gkregex.chas to include <strings.h> over here on linux for thestrcasecmpto be resolved.Related to SU2/2409.