userguide: highlight exception policy effects

Some exception policies can only be applied to entire flows or
individual packets, for some exception scenarios. Make this easier to
read, in the documentation.

Related to
Task OISF#5816

(cherry picked from commit 94b1112)

doc/userguide/configuration/exception-policies.rst

@@ -62,33 +62,40 @@ Specific settings
 Exception policies are implemented for:
 
 .. list-table:: Exception Policy configuration variables
-   :widths: 20, 18, 62
+   :widths: 18, 18, 18, 44
    :header-rows: 1
 
    * - Config setting
      - Policy variable
+     - Affects
      - Expected behavior
    * - stream.memcap
      - memcap-policy
+     - Flow or packet
      - If a stream memcap limit is reached, apply the memcap policy to the packet and/or
        flow.
    * - stream.midstream
      - midstream-policy
+     - Flow
      - If a session is picked up midstream, apply the midstream policy to the flow.
    * - stream.reassembly.memcap
      - memcap-policy
+     - Flow or packet
      - If stream reassembly reaches memcap limit, apply memcap policy to the
        packet and/or flow.
    * - flow.memcap
      - memcap-policy
+     - Packet
      - Apply policy when the memcap limit for flows is reached and no flow could
        be freed up. **Policy can only be applied to the packet.**
    * - defrag.memcap
      - memcap-policy
+     - Packet
      - Apply policy when the memcap limit for defrag is reached and no tracker
        could be picked up. **Policy can only be applied to the packet.**
    * - app-layer
      - error-policy
+     - Flow or packet
      - Apply policy if a parser reaches an error state. Policy can be applied to packet and/or flow.
 
 To change any of these, go to the specific section in the suricata.yaml file