CLEANUP: quic: Useless tests in qc_rx_pkt_handle()

There is no reason to test <qc> nullity at the end of this function because it is
clearly not null, furthermore the trace handle the case where <qc> is null.

Must be backported to 2.7.
diff --git a/src/quic_conn.c b/src/quic_conn.c
index 0e065eb..4b8ac5b 100644
--- a/src/quic_conn.c
+++ b/src/quic_conn.c
@@ -7373,8 +7373,8 @@
 
  drop:
 	HA_ATOMIC_INC(&qc->prx_counters->dropped_pkt);
-	TRACE_PROTO("packet drop", QUIC_EV_CONN_LPKT, qc ? qc : NULL, pkt, NULL, qv);
-	TRACE_LEAVE(QUIC_EV_CONN_LPKT, qc ? qc : NULL);
+	TRACE_PROTO("packet drop", QUIC_EV_CONN_LPKT, qc, pkt, NULL, qv);
+	TRACE_LEAVE(QUIC_EV_CONN_LPKT, qc);
 }
 
 /* This function builds into a buffer at <pos> position a QUIC long packet header,