/boot improvements

[Tetsuya Isaki <isaki%pastel-flower.jp@localhost>]

Hi all,

Recently I improved two for secondary boot loaders.

1) Merge netboot

I merged netboot and boot finally.  Now netboot and boot are very
similar and the only difference is the default kernel which loads.
Both of netboot and boot can load a local kernel and can load a
NFS kernel.

For example, you can select "boot sd0a:netbsd" or "boot nfs:netbsd"
(of course it is necessary to set up network boot environment) on
single /boot which booted from sd0.

2) SCSI host adaptor support

I added SCSI host adaptor selector to "boot" command of /boot.
By this function, /boot which booted from non-SCSI (in other words,
floppy) can load SCSI kernel.

For example, you can select
 "boot fd0a:netbsd" (load from fd0) or
 "boot spc0@cd6a:netbsd" (load from internal SCSI ID=6 CD) or
 "boot nfs:netbsd" (load via network)
on single /boot which booted from fd0.

The host adaptor is set when booted from SCSI.  In this case you
can omit the host adaptor.  For example,
 "boot cd6a:netbsd" (load from internal SCSI ID=6 CD) or
 "boot sd0a:netbsd" (load from internal SCSI ID=0 HD)
on /boot which booted from internal SCSI sd0.

Note: By IOCS limitation, it cannot load kernel from a device of the
host adaptor which different from the host adaptor which booted from.


Please contact me (here) if you have any problem.
Thank you and have fun.
---
Tetsuya Isaki <isaki%pastel-flower.jp@localhost / isaki%NetBSD.org@localhost>