sparc64 needs an entirely untouched, unstripped kernel

[Tom Callaway]

In testing, I've found that sparc64 needs an entirely untouched,
unstripped kernel in order to netboot. The kernels which have gone
through the debuginfo process did not netboot properly, but an untouched
copy of the kernel made right after it is built work fine.

This is a variant of the spec code we've been using in Aurora for a
while, it enables a with-unstripped option, and only enables it for
sparc64. If enabled, it makes a copy, calls it foo-UNSTRIPPED, and
includes it in the %files macro.

If this is ok, let me know, and I'll commit it in rawhide. If there is a
better way to be doing this, also let me know. :)

~spot