The unused dlopen() call is actually useful to enable when lt_dlopen() reports
"file not found" errors for loadable modules that do exist but that Libtool
cannot load successfully due to undefined symbols or other errors.
This inability to correctly report a library loading error is a long-standing
Libtool bug, stemming from Libtool's desire to try and load several
differently named library files until one succeeds, losing true error
information in the process.