[CritFix] Check hyperscan cache sanity before loading

[CritFix] Check hyperscan cache sanity before loading

When regexp database is changed it is possible that hyperscan cache will
contain some invalid or shifted regexps IDs. In this situation, Rspamd
could not correctly detect that such an event occurred and loaded an
incorrect database.

This commit adds strict crc checking that includes:

1. HS ids
2. HS flags
3. HS serialized blob

If this crc fails to match then Rspamd recompiles the corrupted cache
file.