Hi,

This patch fixes the following compilation error:

../.././c++tools/server.cc: In function ‘void server(bool, int,
module_resolver*)’:
../.././c++tools/server.cc:756:69: error: ‘readers’ was not declared
in this scope; did you mean ‘read’?
  756 |               if (active < 0 && sock_fd >= 0 && FD_ISSET
(sock_fd, &readers))
      |
     ^~~~~~~

It was missing a preprocessor condition around this code to work as
the "readers" variable
is created only in a preprocessor condition.

Signed-off-by: Guillaume Gomez <guillaume1.gomez@gmail.com>