They already had a workaround for 64-bit BE.  Since time_t is 64-bit on
all musl platforms, we need it active at all times.

Fixes: #966

No upstream commits in years.  No response to bug reports from other
teams.  Really weird test failures on 32-bit architectures, likely
caused by interactions with signedness and 64-bit integers.

Ref: #873 #880

We still have solr FTS support, so that should be enough.

Didn't bump pkgrel because it hasn't been built/uploaded anywhere yet.

* Tests were not actually being run.  Fix that.

* Port away from CLucene, which is broken on multiple architectures, to
  the Xapian full-text search (FTS) engine.  See #873.

This doesn't fix the test failure, but is more correct.