Opterons with frequency scaling have fully unsynchronized TSCs
running at different frequencies, so using TSCs there is not a good idea. 
Also some other x86 boxes have this problem. gettimeofday should be good 
enough, so just disable it.
Signed-off-by: NAndi Kleen <ak@suse.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>