Core: use c->log while closing connection.

c->pool is not destroyed here since c52408583801.
diff --git a/src/core/ngx_connection.c b/src/core/ngx_connection.c
index 16ba630..a789d8c 100644
--- a/src/core/ngx_connection.c
+++ b/src/core/ngx_connection.c
@@ -1191,10 +1191,7 @@
             level = NGX_LOG_CRIT;
         }
 
-        /* we use ngx_cycle->log because c->log was in c->pool */
-
-        ngx_log_error(level, ngx_cycle->log, err,
-                      ngx_close_socket_n " %d failed", fd);
+        ngx_log_error(level, c->log, err, ngx_close_socket_n " %d failed", fd);
     }
 }