port-arm/54153: emac multicast hash calculation needs ETHER_LOCK

[sc dying <sc.dying%gmail.com@localhost>]

>Number:         54153
>Category:       port-arm
>Synopsis:       emac multicast hash calculation needs ETHER_LOCK
>Confidential:   no
>Severity:       serious
>Priority:       high
>Responsible:    port-arm-maintainer
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Fri May 03 03:00:00 +0000 2019
>Originator:     sc dying <sc.dying%gmail.com@localhost>
>Release:        NetBSD 8.99.37
>Organization:
>Environment:
System: NetBSD 8.99.37 evbarm
Architecture: earmv7hf
Machine: evbarm
Boardtype: NanoPi neo
>Description:
sunxi emac(4) multicast hash calculation needs wrapped with
ETHER_LOCK - ETHER_UNLOCK, especially if NET_MPSAFE is defined.

>How-To-Repeat:

>Fix:
Please add ETHER_LOCK before ETHER_FIRST_MULTI and add ETHER_UNLOCK
after following while loop.

Please pull-up to 8.0, too.