Fix issues introduced by r292275

• Fix panic for etherswitches which don't have a LLADDR.
• Disabled DELAY in unsolicited NDA, which needs further work.
• Fixed missing DELAY in carp_send_na.
• style(9) fix.

Reported by: kp & melifaro
X-MFC-With: r292275
MFC after: 1 month
Sponsored by: Multiplay