port-evbarm/50699: Generic kernels for evbarm don't respect root=$network_device for netboot

[aaron%zadzmo.org@localhost]

>Number:         50699
>Category:       port-evbarm
>Synopsis:       Generic kernels for evbarm don't respect root=$network_device for netboot
>Confidential:   no
>Severity:       non-critical
>Priority:       medium
>Responsible:    port-evbarm-maintainer
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Sun Jan 24 02:30:00 +0000 2016
>Originator:     Aaron B
>Release:        7.0
>Organization:
>Environment:
NetBSD increment 7.0 NetBSD 7.0 (BPI_NETBOOT) #0: Tue Nov 17 00:36:27 EST 2015  aaron@increment:/usr/obj/increment/sys/arch/evbarm/compile/BPI_NETBOOT evbarm

>Description:
While attempting to netboot evbarm devices, the kernel ignores uboot arguments prompts for a root device. 

For example, boot.ini will contain: bootargs="root=awge0"

..and the kernel stops to ask for root/dump/type/path to init, and thus needing manual intervention to finish boot.
root on awge0 type ?

This happens on both a Banana Pi and an Odroid-C1+. Currently, only known workaround is to recompile the kernel with 'root on awge0 type ?' and thus hardcoding the root device.

>How-To-Repeat:

>Fix: