xhci: Expose segment numbers in debugfs

Ring segments have just been amended with a monotonically increasing
number.

To allow developers to inspect the segment numbers and ensure
correctness in particular after ring expansion, expose them in each
ring's "trbs" file in debugfs.

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20231019102924.2797346-9-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Author: l1k

drivers/usb/host/xhci-debugfs.c

@@ -204,7 +204,7 @@ static void xhci_ring_dump_segment(struct seq_file *s,
 	for (i = 0; i < TRBS_PER_SEGMENT; i++) {
 		trb = &seg->trbs[i];
 		dma = seg->dma + i * sizeof(*trb);
-		seq_printf(s, "%pad: %s\n", &dma,
+		seq_printf(s, "%2u %pad: %s\n", seg->num, &dma,
 			   xhci_decode_trb(str, XHCI_MSG_MAX, le32_to_cpu(trb->generic.field[0]),
 					   le32_to_cpu(trb->generic.field[1]),
 					   le32_to_cpu(trb->generic.field[2]),