All PPC ports broken since 5.99.61

[Frank Wille <frank%phoenix.owl.de@localhost>]

Since 5.99.61 no PPC machine can boot a recent kernel anymore.
They hang early, directly after cpu_startup(), probably in sysctl_init().

From a sandpoint system:
NetBSD 5.99.62 (GENERIC) #5: Mon Jan 30 20:51:52 CET 2012
        
frank%compaq.owl.de@localhost:/home/frank/netbsd/current/src/sys/arch/sandpoint/compile/obj/GENERIC
Model: synology
total memory = 32768 KB
avail memory = 27584 KB
OpenPIC Version 1.2: Supports 1 CPUs and 26 interrupt sources.
sysctl_createv: sysctl_create(mapped_files) returned 12

I guess it has something to do with the major UVM/kmem/vmem changes?

-- 
Frank Wille