Get absoulte config file path before processig 'dir'.

The code tried to obtain the configuration file absolute path after
processing the configuration file. However if config file was a relative
path and a "dir" statement was processed reading the config, the absolute
path obtained was wrong.

With this fix the absolute path is obtained before processing the
configuration while the server is still in the original directory where
it was executed.

src/redis.c

@@ -3030,10 +3030,10 @@ int main(int argc, char **argv) {
             }
             j++;
         }
+        if (configfile) server.configfile = getAbsolutePath(configfile);
         resetServerSaveParams();
         loadServerConfig(configfile,options);
         sdsfree(options);
-        if (configfile) server.configfile = getAbsolutePath(configfile);
     } else {
         redisLog(REDIS_WARNING, "Warning: no config file specified, using the default config. In order to specify a config file use %s /path/to/%s.conf", argv[0], server.sentinel_mode ? "sentinel" : "redis");
     }