scsi: iscsi: Fix incorrect error path labels for flashnode operations

Correct the error handling goto labels used when host lookup fails in
various flashnode-related event handlers:

 - iscsi_new_flashnode()
 - iscsi_del_flashnode()
 - iscsi_login_flashnode()
 - iscsi_logout_flashnode()
 - iscsi_logout_flashnode_sid()

scsi_host_put() is not required when shost is NULL, so jumping to the
correct label avoids unnecessary operations. These functions previously
jumped to the wrong goto label (put_host), which did not match the
intended cleanup logic.

Use the correct exit labels (exit_new_fnode, exit_del_fnode, etc.) to
ensure proper error handling.  Also remove the unused put_host label
under iscsi_new_flashnode() as it is no longer needed.

No functional changes beyond accurate error path correction.

Fixes: c6a4bb2 ("[SCSI] scsi_transport_iscsi: Add flash node mgmt support")
Signed-off-by: Alok Tiwari <alok.a.tiwari@oracle.com>
Link: https://lore.kernel.org/r/20250530193012.3312911-1-alok.a.tiwari@oracle.com
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

Author: aloktiwa

drivers/scsi/scsi_transport_iscsi.c

@@ -3499,7 +3499,7 @@ static int iscsi_new_flashnode(struct iscsi_transport *transport,
 		pr_err("%s could not find host no %u\n",
 		       __func__, ev->u.new_flashnode.host_no);
 		err = -ENODEV;
-		goto put_host;
+		goto exit_new_fnode;
 	}
 
 	index = transport->new_flashnode(shost, data, len);
@@ -3509,7 +3509,6 @@ static int iscsi_new_flashnode(struct iscsi_transport *transport,
 	else
 		err = -EIO;
 
-put_host:
 	scsi_host_put(shost);
 
 exit_new_fnode:
@@ -3534,7 +3533,7 @@ static int iscsi_del_flashnode(struct iscsi_transport *transport,
 		pr_err("%s could not find host no %u\n",
 		       __func__, ev->u.del_flashnode.host_no);
 		err = -ENODEV;
-		goto put_host;
+		goto exit_del_fnode;
 	}
 
 	idx = ev->u.del_flashnode.flashnode_idx;
@@ -3576,7 +3575,7 @@ static int iscsi_login_flashnode(struct iscsi_transport *transport,
 		pr_err("%s could not find host no %u\n",
 		       __func__, ev->u.login_flashnode.host_no);
 		err = -ENODEV;
-		goto put_host;
+		goto exit_login_fnode;
 	}
 
 	idx = ev->u.login_flashnode.flashnode_idx;
@@ -3628,7 +3627,7 @@ static int iscsi_logout_flashnode(struct iscsi_transport *transport,
 		pr_err("%s could not find host no %u\n",
 		       __func__, ev->u.logout_flashnode.host_no);
 		err = -ENODEV;
-		goto put_host;
+		goto exit_logout_fnode;
 	}
 
 	idx = ev->u.logout_flashnode.flashnode_idx;
@@ -3678,7 +3677,7 @@ static int iscsi_logout_flashnode_sid(struct iscsi_transport *transport,
 		pr_err("%s could not find host no %u\n",
 		       __func__, ev->u.logout_flashnode.host_no);
 		err = -ENODEV;
-		goto put_host;
+		goto exit_logout_sid;
 	}
 
 	session = iscsi_session_lookup(ev->u.logout_flashnode_sid.sid);