9696 add /etc/system.d support
Reviewed by: Dan Fields <dan.fields@nexenta.com>
Reviewed by: Roman Strashkin <roman.strashkin@nexenta.com>
Reviewed by: Cynthia Eastham <cynthia.eastham@nexenta.com>

*** 14,23 ****
--- 14,24 ----
  etc/name_to_major
  etc/name_to_sysnum
  etc/path_to_inst
  etc/rtc_config
  etc/system
+ etc/system.d
  etc/hostid
  kernel
  platform/i86hvm/kernel
  platform/i86pc/kernel
  platform/i86xpv/kernel