Correct `get_claimable_balance` version info

Correct `get_claimable_balance` version info

5a8ede09fb3c8bbcd8694d94c12dac9ea7485537 updated the documentation
on `get_claimable_balance` to note that if a channel went on-chain
with an LDK version older than 0.0.108 some
counterparty-revoked-output claimable balances my be missing.
However, this failed to account for the fact that we rely on the
entirely-new-in-0.0.111
`confirmed_commitment_tx_counterparty_output` field for some
balances as well.

Thus, the comment should have been in terms of 0.0.111, not
0.0.108.