PARTIAL: typofixes (found by misspell_fixer)

Upstream: 9f68ed6b6d1a9c6436ce37913666165f2b180ee3 (PR #6539)

src/rpcserver.cpp

@@ -673,7 +673,7 @@ void StartRPCThreads()
         vEndpoints.push_back(ip::tcp::endpoint(boost::asio::ip::address_v6::any(), defaultPort));
         vEndpoints.push_back(ip::tcp::endpoint(boost::asio::ip::address_v4::any(), defaultPort));
         // Prefer making the socket dual IPv6/IPv4 instead of binding
-        // to both addresses seperately.
+        // to both addresses separately.
         bBindAny = true;
     }