textproc/redland: Unbreak BDB option

Before [1] we had former port devel/virtuoso explicitly disabled as a
pseudo-option, but this configure argument was lost in that commit. The
seemingly buggy configure script tries to use virtuoso despite its
non-existence.

rdf_storage_virtuoso.c:55:10: fatal error: 'sql.h' file not found

[1] https://cgit.freebsd.org/ports/commit/?id=134cdd54850031bfdc8202d27b1a69b2839d94bb

PR: 275700
Reported by: <andy@neu.net>