Drop freebsd/inotify.{cpp,h} on FreeBSD < 1500050 (no native sys/inotify.h).

--- osquery/events/CMakeLists.txt.orig
+++ osquery/events/CMakeLists.txt
@@ -59,7 +59,6 @@
       audit_flags.cpp
       file_events_flags.cpp
       freebsd/devd.cpp
-      freebsd/inotify.cpp
       freebsd/openbsm.cpp
     )

@@ -188,7 +187,6 @@
   elseif(DEFINED PLATFORM_FREEBSD)
     set(platform_public_header_files
       freebsd/devd.h
-      freebsd/inotify.h
       freebsd/openbsm.h
     )