Replace perl she-bangline

Created by: fendor

On some Unix variations, perl is not installed in /usr/bin/perl, e.g. in NixOS. This forced me, to manually replace all occurrences of #!/usr/bin/perl to #!/usr/bin/env perl. Then I was able to successfully compile the likwid tools.

Would it be possible to replace #!/usr/bin/perl in upstream with #!/usr/bin/env perl? It should have the same functionality while simplifying the installation process for some Operating Systems and likwid is then, overall, more portable.