Implement fanotify_init and fanotify_mark decoding

Implement fanotify_init and fanotify_mark decoding

* fanotify.c: New file.
* linux/fanotify.h: Likewise.
* Makefile.am (strace_SOURCES): Add fanotify.c.
(EXTRA_DIST): Add linux/fanotify.h.
* defs.h (print_dirfd): New prototype.
* file.c (print_dirfd): Export.
* linux/dummy.h (sys_fanotify_init, sys_fanotify_mark): Remove.
* linux/syscall.h (sys_fanotify_init, sys_fanotify_mark): New
prototypes.
* pathtrace.c (pathtrace_match): Handle sys_fanotify_init and
sys_fanotify_mark.