fanotify: fanotify_init syscall declaration

This patch defines a new syscall fanotify_init() of the form:

int sys_fanotify_init(unsigned int flags, unsigned int event_f_flags,
		      unsigned int priority)

This syscall is used to create and fanotify group.  This is very similar to
the inotify_init() syscall.

Signed-off-by: Eric Paris <eparis@redhat.com>

kernel/sys_ni.c

@@ -181,3 +181,6 @@ cond_syscall(sys_eventfd2);
 
 /* performance counters: */
 cond_syscall(sys_perf_event_open);
+
+/* fanotify! */
+cond_syscall(sys_fanotify_init);