POSIX.1-2008 changed the st_atim, st_mtim, and st_ctime members of the
struct stat from time_t to struct timespec and because not all operating
systems already implemented this version of the standard or historically
deviated to include own nanosecond precision in the structure.

The autoconf script used to include <sys/fcntl.h> which contradicts
POSIX.1 as it mandates <sys/stat.h> inclusion.  Change the autoconf
check to include <sys/stat.h>.

Also fix the missing AC_MSG_RESULT([yes/no]) in the check.