testsuite: let stat.h take care of stat64
testsuite: let stat.h take care of stat64

This fixes testsuite build in 32 bits machines.

lucasdemarchi/kmod,lpereira/kmod,Distrotech/kmod,pmmccorm/kmod,lpereira/kmod,Distrotech/kmod,lpereira/kmod,pmmccorm/kmod,Distrotech/kmod,pmmccorm/kmod,lucasdemarchi/kmod,lucasdemarchi/kmod