Fix HAVE_DCMTK_LOG4CPLUS_LOGGER test on multi-configuration build system.

This a follow-up of commit 483dca075.

See inlined comment for details.

See #421
Merge branch '421-fix-dcmtk-log4cplus-logger-try-compile-with-multi-config'

* 421-fix-dcmtk-log4cplus-logger-try-compile-with-multi-config:
  Fix HAVE_DCMTK_LOG4CPLUS_LOGGER test on multi-configuration build system.