Build fails on armv7 on FreeBSD: undefined symbol: _Unwind_SjLj_Register

[yurivict]

Build fails on armv7 on FreeBSD:

= note: ld: error: undefined symbol: _Unwind_SjLj_Register
          >>> referenced by blob_contents.cc
          >>>               blob_contents.o:(rocksdb::BlobContents::GetCacheItemHelper()) in archive /wrkdirs/usr/ports/finance/electrs/work/rustcjPjR5M/libelectrs_librocksdb_sys-327b4b91bc3e735a.rlib
          >>> referenced by blob_contents.cc
          >>>               blob_contents.o:(void (*rocksdb::GetCacheEntryDeleterForRole<rocksdb::BlobContents, (rocksdb::CacheEntryRole)11>())(rocksdb::Slice const&, void*)) in archive /wrkdirs/usr/ports/finance/electrs/work/rustcjPjR5M/libelectrs_librocksdb_sys-327b4b91bc3e735a.rlib
          >>> referenced by blob_contents.cc
          >>>               blob_contents.o:(rocksdb::BlobContents::CreateCallback(std::__1::unique_ptr<char [], rocksdb::CustomDeleter>&&, void const*, unsigned int, void**, unsigned int*)) in archive /wrkdirs/usr/ports/finance/electrs/work/rustcjPjR5M/libelectrs_librocksdb_sys-327b4b91bc3e735a.rlib

log

FreeBSD does not use SjLj based exception handling by default on arm platforms.

See the further details in this downstream bug report: https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=283841