Use more curl_off_t variables when doing the progress meter calculations and

argument passing and try to convert to double only when providing data to the
external world.

lib/ftp.c

@@ -1821,7 +1821,7 @@ CURLcode Curl_ftp_nextconnect(struct connectdata *conn)
     /* When we know we're uploading a specified file, we can get the file
        size prior to the actual upload. */
 
-    Curl_pgrsSetUploadSize(data, (double)data->set.infilesize);
+    Curl_pgrsSetUploadSize(data, data->set.infilesize);
 
     result = Curl_Transfer(conn, -1, -1, FALSE, NULL, /* no download */
                            SECONDARYSOCKET, bytecountp);