[PATCH] gpib: mark pnp_device_id tables as __maybe_unused

[Arnd Bergmann <arnd@kernel.org>]

From: Arnd Bergmann <arnd@arndb.de>

This variable is not referenced in either of these two drivers driver,
causing a warning when they are built-in and W=1 warnings are enabled
with gcc:

drivers/staging/gpib/tnt4882/tnt4882_gpib.c:1507:35: error: 'tnt4882_pnp_table' defined but not used [-Werror=unused-const-variable=]
 1507 | static const struct pnp_device_id tnt4882_pnp_table[] = {
      |                                   ^~~~~~~~~~~~~~~~~
drivers/staging/gpib/hp_82341/hp_82341.c:811:35: error: 'hp_82341_pnp_table' defined but not used [-Werror=unused-const-variable=]
  811 | static const struct pnp_device_id hp_82341_pnp_table[] = {

The MODULE_DEVICE_TABLE() entry does have the effect of loading
the module when the PNP device is detected, so it is still needed
for the modular case.

Ideally the drivers should be converted to pnp_register_driver(),
which would lead to the ID table actually being used.

As a simpler workaround, add a __maybe_unused annotation to shut
up the warning.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 drivers/staging/gpib/hp_82341/hp_82341.c    | 2 +-
 drivers/staging/gpib/tnt4882/tnt4882_gpib.c | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/staging/gpib/hp_82341/hp_82341.c b/drivers/staging/gpib/hp_82341/hp_82341.c
index 800f99c05566..7284311e04e2 100644
--- a/drivers/staging/gpib/hp_82341/hp_82341.c
+++ b/drivers/staging/gpib/hp_82341/hp_82341.c
@@ -808,7 +808,7 @@ static void hp_82341_detach(gpib_board_t *board)
 	hp_82341_free_private(board);
 }
 
-static const struct pnp_device_id hp_82341_pnp_table[] = {
+static __maybe_unused const struct pnp_device_id hp_82341_pnp_table[] = {
 	{.id = "HWP1411"},
 	{.id = ""}
 };
diff --git a/drivers/staging/gpib/tnt4882/tnt4882_gpib.c b/drivers/staging/gpib/tnt4882/tnt4882_gpib.c
index 2e1c3cbebaca..cf3b2a0eb93d 100644
--- a/drivers/staging/gpib/tnt4882/tnt4882_gpib.c
+++ b/drivers/staging/gpib/tnt4882/tnt4882_gpib.c
@@ -1390,7 +1390,7 @@ static struct pci_driver tnt4882_pci_driver = {
 	.probe = &tnt4882_pci_probe
 };
 
-static const struct pnp_device_id tnt4882_pnp_table[] = {
+static __maybe_unused const struct pnp_device_id tnt4882_pnp_table[] = {
 	{.id = "NICC601"},
 	{.id = ""}
 };
-- 
2.39.5