Follow-up from "Part of "Static code analysis of OPAL""

The following discussion from !363 (merged) should be addressed:

• @snuverink_j started a discussion: (+1 comment)

  @ext-calvo_p : this include shouldn't have been removed as line 95 uses gettimeofday which is part of <sys/time.h>: https://linux.die.net/man/2/gettimeofday. On Mac I get a compile error without the include.