Add src/wallet/* code to wallet:: namespace

src/wallet/dump.h

@@ -7,11 +7,12 @@
 
 #include <fs.h>
 
-class CWallet;
-
 struct bilingual_str;
 
+namespace wallet {
+class CWallet;
 bool DumpWallet(CWallet& wallet, bilingual_str& error);
 bool CreateFromDump(const std::string& name, const fs::path& wallet_path, bilingual_str& error, std::vector<bilingual_str>& warnings);
+} // namespace wallet
 
 #endif // BITCOIN_WALLET_DUMP_H