We can tell this more generically because the count of revocations
received != count of commitments sent. This is the correct condition
which allows us to restore the test we had to eliminate in
c3cb7f1c85.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
The wire protocol uses this, in the assumption that we'll never see feerates
in excess of 4294967 satoshi per kiloweight.
So let's use that consistently internally as well.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>