Fixing pidfile location discrepancy introduced in 3.10.2

* in dspam.c, they have the application default to looking for the
  pidfile in /var/run/dspam/dspam.pid if none is specified in the
  configs
* however, in the configs it states the default for the pidfile is
  /var/run/dspam.pid (which is where it always has been)
* it looks like someone introduced an incorrect location in dspam.c
  by mistake, we should probably push that upstream