CLEANUP: quic: fix headers

Clean up quic sources by adjusting headers list included depending
on the actual dependency of each source file.

On some occasion, xprt_quic.h was removed from included list. This is
useful to help reducing the dependency on this single file and cleaning
up QUIC haproxy architecture.

This should be backported up to 2.6.
diff --git a/src/qmux_trace.c b/src/qmux_trace.c
index 72a8f1b..7899bff 100644
--- a/src/qmux_trace.c
+++ b/src/qmux_trace.c
@@ -5,6 +5,7 @@
 #include <haproxy/connection.h>
 #include <haproxy/chunk.h>
 #include <haproxy/mux_quic.h>
+#include <haproxy/quic_frame-t.h>
 
 /* trace source and events */
 static void qmux_trace(enum trace_level level, uint64_t mask,