xyz-modem: Put xyzModem_stream_close debug diagnostic message into ZM_DEBUG()

This is how all other debug / diagnostic messages are handled.

Signed-off-by: Pali Rohár <pali@kernel.org>
diff --git a/common/xyzModem.c b/common/xyzModem.c
index 631c44e..c200c9f 100644
--- a/common/xyzModem.c
+++ b/common/xyzModem.c
@@ -608,10 +608,10 @@
 void
 xyzModem_stream_close (int *err)
 {
-  diag_printf
+  ZM_DEBUG (zm_dprintf
     ("xyzModem - %s mode, %d(SOH)/%d(STX)/%d(CAN) packets, %d retries\n",
      xyz.crc_mode ? "CRC" : "Cksum", xyz.total_SOH, xyz.total_STX,
-     xyz.total_CAN, xyz.total_retries);
+     xyz.total_CAN, xyz.total_retries));
   ZM_DEBUG (zm_flush ());
 }