cli: use GetWalletBalances() functionality for -getinfo

and replace GetBoolArg with IsArgSet as we only want
to know if the arg is passed; we do not need the value.

Github-Pull: bitcoin#18594
Rebased-From: afce85e

src/bitcoin-cli.cpp

@@ -530,9 +530,8 @@ static int CommandLineRPC(int argc, char *argv[])
         }
         std::unique_ptr<BaseRequestHandler> rh;
         std::string method;
-        if (gArgs.GetBoolArg("-getinfo", false)) {
+        if (gArgs.IsArgSet("-getinfo")) {
             rh.reset(new GetinfoRequestHandler());
-            method = "";
         } else {
             rh.reset(new DefaultRequestHandler());
             if (args.size() < 1) {
@@ -565,6 +564,9 @@ static int CommandLineRPC(int argc, char *argv[])
                 }
             }
         } else {
+            if (gArgs.IsArgSet("-getinfo") && !gArgs.IsArgSet("-rpcwallet")) {
+                GetWalletBalances(result); // fetch multiwallet balances and append to result
+            }
             // Result
             if (result.isNull()) {
                 strPrint = "";