Bluetooth: add printf format attribute to hci_set_[fh]w_info()

Commit 5177a838 ("Bluetooth: Add debugfs fields for hardware and
firmware info") introduced hci_set_hw_info() and hci_set_fw_info().
These functions use kvasprintf_const() but are not marked with a
__printf attribute.  Adding such an attribute helps detecting issues
related to printf-formatting at build time.
Signed-off-by: Nicolas Iooss <nicolas.iooss_linux@m4x.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

include/net/bluetooth/hci_core.h

@@ -1028,8 +1028,8 @@ int hci_resume_dev(struct hci_dev *hdev);
 int hci_reset_dev(struct hci_dev *hdev);
 int hci_recv_frame(struct hci_dev *hdev, struct sk_buff *skb);
 int hci_recv_diag(struct hci_dev *hdev, struct sk_buff *skb);
-void hci_set_hw_info(struct hci_dev *hdev, const char *fmt, ...);
-void hci_set_fw_info(struct hci_dev *hdev, const char *fmt, ...);
+__printf(2, 3) void hci_set_hw_info(struct hci_dev *hdev, const char *fmt, ...);
+__printf(2, 3) void hci_set_fw_info(struct hci_dev *hdev, const char *fmt, ...);
 int hci_dev_open(__u16 dev);
 int hci_dev_close(__u16 dev);
 int hci_dev_do_close(struct hci_dev *hdev);