unwanted sideeffects in the RB_ASKNAME case. This fixes PR/46732.
No longer wrap MD cpu_rootconf(), as hp300 port stores reboot information
as a side effect. Instead call MI rootconf() from MD code which makes
rootconf() now a wrapper to setroot().
Adjust several MD routines to set the global booted_device,booted_partition
variables instead of passing partial information to setroot().
Make cpu_rootconf(9) describe the calling order.
8ce4433821