getpid.sh: Fix testcase error for Debian using sbuild

getpid.sh: Fix testcase error for Debian using sbuild

When

 * building the ngircd Debian package (on Linux at least) and
 * using the sbuild build system,

the command "ps -af" does not include the commands running inside the
sbuild system. Therefore, start-server.sh will report a fail as getpid.sh
cannot not  find the ./T-ngircd1 just started although it's actually
running. This results in a funny build log ...

         starting server 1 ... failure!
   FAIL: start-server1
         running connect-test ... ok.
   PASS: connect-test

The self-test of getpid.sh however will likely succeed as it's happy if
it sees any process with "sh" somewhere in the name. Things go downhill
from there.

The confusing things are:

  * The alternative cowbuilder/pbuilder does not have this problem.
  * The alternative usage "ps ax" does fine.

So, as a quick hack, the patch attached adds another switch to getpid.sh.