Merge bitcoin/bitcoin#33343: help: enrich help text for -loadblock

2e041b4 help: enrich help text for `-loadblock` (Hao Xu)

Pull request description:

  `-loadblock` doesn't support XOR-ed files, mention it in its help text to avoid troubles for users.

ACKs for top commit:
  maflcko:
    lgtm ACK 2e041b4
  sedited:
    ACK 2e041b4

Tree-SHA512: 1883824c15687799d60ddabc53d5dc2c274e56c8292da5e7e412adaef65abf70c7f778ef7675c65f738c1e4855e5b0f929e87631b0a52695873e58f8245b3a8d

Author: fanquake

src/init.cpp

@@ -506,7 +506,7 @@ void SetupServerArgs(ArgsManager& argsman, bool can_listen_ipc)
     argsman.AddArg("-dbcache=<n>", strprintf("Maximum database cache size <n> MiB (minimum %d, default: %d). Make sure you have enough RAM. In addition, unused memory allocated to the mempool is shared with this cache (see -maxmempool).", MIN_DB_CACHE >> 20, node::GetDefaultDBCache() >> 20), ArgsManager::ALLOW_ANY, OptionsCategory::OPTIONS);
     argsman.AddArg("-includeconf=<file>", "Specify additional configuration file, relative to the -datadir path (only useable from configuration file, not command line)", ArgsManager::ALLOW_ANY, OptionsCategory::OPTIONS);
     argsman.AddArg("-allowignoredconf", strprintf("For backwards compatibility, treat an unused %s file in the datadir as a warning, not an error.", BITCOIN_CONF_FILENAME), ArgsManager::ALLOW_ANY, OptionsCategory::OPTIONS);
-    argsman.AddArg("-loadblock=<file>", "Imports blocks from external file on startup", ArgsManager::ALLOW_ANY, OptionsCategory::OPTIONS);
+    argsman.AddArg("-loadblock=<file>", "Imports blocks from an external file on startup. Obfuscated blocks are not supported.", ArgsManager::ALLOW_ANY, OptionsCategory::OPTIONS);
     argsman.AddArg("-maxmempool=<n>", strprintf("Keep the transaction memory pool below <n> megabytes (default: %u)", DEFAULT_MAX_MEMPOOL_SIZE_MB), ArgsManager::ALLOW_ANY, OptionsCategory::OPTIONS);
     argsman.AddArg("-mempoolexpiry=<n>", strprintf("Do not keep transactions in the mempool longer than <n> hours (default: %u)", DEFAULT_MEMPOOL_EXPIRY_HOURS), ArgsManager::ALLOW_ANY, OptionsCategory::OPTIONS);
     argsman.AddArg("-minimumchainwork=<hex>", strprintf("Minimum work assumed to exist on a valid chain in hex (default: %s, testnet3: %s, testnet4: %s, signet: %s)", defaultChainParams->GetConsensus().nMinimumChainWork.GetHex(), testnetChainParams->GetConsensus().nMinimumChainWork.GetHex(), testnet4ChainParams->GetConsensus().nMinimumChainWork.GetHex(), signetChainParams->GetConsensus().nMinimumChainWork.GetHex()), ArgsManager::ALLOW_ANY | ArgsManager::DEBUG_ONLY, OptionsCategory::OPTIONS);