add cpuserver to the initramfs; leave cpu in there for now
add cpuserver to the initramfs; leave cpu in there for now

cpuserver is our new smaller-footprint server we needed for atomic pi.

Signed-off-by: Ronald G. Minnich <f569d0af9a3481c4007b95c7180d6c41009f2513@gmail.com>

u-root/cpu,u-root/cpu,u-root/cpu