xfsdump: fix on-media inventory stream packing

With the on-media inventory now being restored for multiple streams we
can see that the restored streams both claim to be for /dev/nst0.

[root@rhel8 xfsdump-dev]# xfsdump -L "Test" -f /dev/nst0 -M tape1 -f /dev/nst1 -M tape2 /boot
...
[root@rhel8 ~]# rm -rf /var/lib/xfsdump/inventory
[root@rhel8 xfsdump-dev]# restore/xfsrestore -L Test -f /dev/nst0 -f /dev/nst1 /tmp/test
restore/xfsrestore: using scsi tape (drive_scsitape) strategy
restore/xfsrestore: using scsi tape (drive_scsitape) strategy
restore/xfsrestore: version 3.1.10 (dump format 3.0) - type ^C for status and control
...
restore/xfsrestore: Restore Summary:
restore/xfsrestore:   stream 0 /dev/nst0 OK (success)
restore/xfsrestore:   stream 1 /dev/nst1 ALREADY_DONE (another stream completed the operation)
restore/xfsrestore: Restore Status: SUCCESS
[root@rhel8 xfsdump-dev]# xfsdump -I
file system 0:
	fs id:		26dd5aa0-b901-4cf5-9b68-0c5753cb3ab8
	session 0:
		mount point:	rhel8:/boot
		device:		rhel8:/dev/sda1
		time:		Fri Oct 14 18:31:40 2022
		session label:	"Test"
		session id:	96538a3d-2af8-4a79-8865-afec6e3e55f4
		level:		0
		resumed:	NO
		subtree:	NO
		streams:	2
		stream 0:
			pathname:	/dev/nst0
			start:		ino 133 offset 0
			end:		ino 28839 offset 0
			interrupted:	YES
			media files:	1
			media file 0:
				mfile index:	0
				mfile type:	data
				mfile size:	165675008
				mfile start:	ino 133 offset 0
				mfile end:	ino 28839 offset 0
				media label:	"tape1"
				media id:	8a9d0ced-61f6-4332-a0c1-f1e38641c4e6
		stream 1:
			pathname:	/dev/nst0
			start:		ino 133 offset 0
			end:		ino 28839 offset 0
			interrupted:	YES
			media files:	1
			media file 0:
				mfile index:	0
				mfile type:	data
				mfile size:	166723584
				mfile start:	ino 28839 offset 0
				mfile end:	ino 1572997 offset 0
				media label:	"tape2"
				media id:	7d569377-6bfb-4c02-b299-4dbe753bb048
xfsdump: Dump Status: SUCCESS
[root@rhel8 xfsdump-dev]#

Fix this by indexing the stream being packed for the on-media inventory.

Signed-off-by: Donald Douwsma <ddouwsma@redhat.com>
Suggested-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
diff --git a/inventory/inv_stobj.c b/inventory/inv_stobj.c
index 42b86dc..d6aedf2 100644
--- a/inventory/inv_stobj.c
+++ b/inventory/inv_stobj.c
@@ -798,7 +798,7 @@
 	sesbuf += sizeof(invt_session_t);
 
 	for (i = 0; i < ses->s_cur_nstreams; i++) {
-		xlate_invt_stream(strms, (invt_stream_t *)sesbuf, 1);
+		xlate_invt_stream(&strms[i], (invt_stream_t *)sesbuf, 1);
 		sesbuf += sizeof(invt_stream_t);
 	}