Also, the munging is extended by inserting an instruction that branches
past the header, so the same boot image can be used on all supported
sun platforms.
Since uname currently does not allow to discriminate different sparc
models, we use `sysctl.hw.cpumodel' to do this somewhat heuristicly:
if the returned strings starts with "SUN4-" a sun4 architecture is
assumed. This information is used to determine whether or not to strip
the a.out header off the 1st-stage bootblocks.
pk