One of the things we can't fake on PPC is the timer speed. So
we need to extract the frequency information from the host and
put it back into the guest device tree.

Luckily, we already have functions for that from the non-pseries
targets, so all we need to do is to connect the dots and the guest
suddenly gets to know its real timer speeds.
Signed-off-by: NAlexander Graf <agraf@suse.de>