IFCAP_WOL

[SAITOH Masanobu <masanobu%iij.ad.jp@localhost>]

 Hello.

 As I wrote in the commit message for if_wm.c rev. 1.203. I've succeeded
waking up from suspend(S3) by the Magic Packet. I tested on my ThinkPad X61.

 The function is disabled by default because it may wastes a battery's
capacity in a notebook. So I think it's a good solution to introduce FreeBSD's
IFCAP_WOL to NetBSD.

 Any objections?

----------------------------------------------------------
                SAITOH Masanobu (masanobu%iij.ad.jp@localhost
                                  msaitoh%netbsd.org@localhost)