Remove unnecessary #ifdefs and dead code in Spider.
ha_spider::start_bulk_insert without uint flags is not used because
handler::ha_start_bulk_insert calls start_bulk_insert for each storage engine
with flags. Therefore, dead code and #ifdef related to
SPIDER_HANDLER_START_BULK_INSERT_HAS_FLAGS have been removed.

Remove the dead-code, in Spider, which is related to the Spider's
Oracle OCI support. The code has been disabled for a long time and
it is unlikely that the code will be enabled.

This reverts commit c9beef43, because
we have OpenSSL 3.0 support here.