exceptions: move midstream stats to common counter

Part of making the exception policy stats counters more search
friendly.

Task #7185

(cherry picked from commit 78b16a9b76)

etc/schema.json

@@ -4969,6 +4969,11 @@
                         },
                         "tcp": {
                             "type": "object",
+                            "midstream": {
+                                "description":
+                                        "How many times midstream exception policy was applied, and which one",
+                                "$ref": "#/$defs/exceptionPolicy"
+                            },
                             "ssn_memcap": {
                                 "description":
                                         "How many times session memcap exception policy was applied, and which one",
@@ -5324,11 +5329,6 @@
                         "midstream_pickups": {
                             "type": "integer"
                         },
-                        "midstream_exception_policy": {
-                            "description":
-                                    "How many times midstream exception policy was applied, and which one",
-                            "$ref": "#/$defs/exceptionPolicy"
-                        },
                         "no_flow": {
                             "type": "integer"
                         },

src/stream-tcp.c

@@ -5976,11 +5976,11 @@ TmEcode StreamTcpThreadInit(ThreadVars *tv, void *initdata, void **data)
     if (stream_config.midstream) {
         ExceptionPolicySetStatsCounters(tv, &stt->counter_tcp_midstream_eps,
                 &stream_midstream_enabled_eps_stats, stream_config.midstream_policy,
-                "tcp.midstream_exception_policy.", IsMidstreamExceptionPolicyStatsValid);
+                "exception_policy.tcp.midstream.", IsMidstreamExceptionPolicyStatsValid);
     } else {
         ExceptionPolicySetStatsCounters(tv, &stt->counter_tcp_midstream_eps,
                 &stream_midstream_disabled_eps_stats, stream_config.midstream_policy,
-                "tcp.midstream_exception_policy.", IsMidstreamExceptionPolicyStatsValid);
+                "exception_policy.tcp.midstream.", IsMidstreamExceptionPolicyStatsValid);
     }
 
     stt->counter_tcp_wrong_thread = StatsRegisterCounter("tcp.pkt_on_wrong_thread", tv);