detect: don't run pkt sigs on ffr pkts
Last packet from the TLS TCP session moves TCP state to CLOSED.
This flags the app-layer with APP_LAYER_PARSER_EOF_TS or
APP_LAYER_PARSER_EOF_TC depending on the direction of the final packet.
This flag will just have been set in a single direction.
This leads to the last packet updating the inspect id in that packets
direction.
At the end of the TLS session a pseudo packet is created, because:
- flow has ended
- inspected tx id == 0, for at least one direction
- total txs is 1
Then a packet rule matches:
```
alert tcp any any -> any 443 (flow: to_server; \
flowbits:isset,tls_error; \
sid:
09901033; rev:1; \
msg:"Allow TLS error handling (outgoing packet)"; )
```
The `SIG_MASK_REQUIRE_REAL_PKT` is not preventing the match, as the
`flowbits` keyword doesn't set it.
To avoid this match. This patch skips signatures of the `SIG_TYPE_PKT`
for flow end packets.
Ticket: #7318.