hsmd: Add hsmd_forget_channel to tell hsmd to delete a channel#101

ksedgwic wants to merge 3 commits into2023-11-remote-hsmd-v23.11lightning-signer/c-lightning:2023-11-remote-hsmd-v23.11from

2023-12-hsmd-forget-channellightning-signer/c-lightning:2023-12-hsmd-forget-channelCopy head branch name to clipboard