singleipconnect: Update *sockp for all CURLE_OK

The 56b7c87c7 change left a case where a good sockfd was not copied to
*sockp before returning with CURLE_OK

lib/connect.c

@@ -970,6 +970,8 @@ singleipconnect(struct connectdata *conn,
       break;
     }
   }
+  else
+    *sockp = sockfd;
 
   return CURLE_OK;
 }