[PATCH v2 2/2] dmaengine: dw: dmamux: Fix build without CONFIG_OF

[Miquel Raynal <miquel.raynal@bootlin.com>]

When built without OF support, of_match_node() expands to NULL, which
produces the following output:
>> drivers/dma/dw/rzn1-dmamux.c:105:34: warning: unused variable 'rzn1_dmac_match' [-Wunused-const-variable]
   static const struct of_device_id rzn1_dmac_match[] = {

One way to silence the warning is to enclose the structure definition
with an #ifdef CONFIG_OF/#endif block.

In order to keep the harmony in the driver, the second match table is
also enclosed with the same #ifdef CONFIG_OF/#endif block and the use of
the match table forwarded by the of_match_ptr() macro.

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
---

Changes in v2:
* Used the #ifdef solution rather than the __maybe_unused keyword.

 drivers/dma/dw/rzn1-dmamux.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/dma/dw/rzn1-dmamux.c b/drivers/dma/dw/rzn1-dmamux.c
index 0ce4fb58185e..6ab33614e91e 100644
--- a/drivers/dma/dw/rzn1-dmamux.c
+++ b/drivers/dma/dw/rzn1-dmamux.c
@@ -102,10 +102,12 @@ static void *rzn1_dmamux_route_allocate(struct of_phandle_args *dma_spec,
 	return ERR_PTR(ret);
 }
 
+#ifdef CONFIG_OF
 static const struct of_device_id rzn1_dmac_match[] = {
 	{ .compatible = "renesas,rzn1-dma" },
 	{}
 };
+#endif
 
 static int rzn1_dmamux_probe(struct platform_device *pdev)
 {
@@ -136,16 +138,18 @@ static int rzn1_dmamux_probe(struct platform_device *pdev)
 				      &dmamux->dmarouter);
 }
 
+#ifdef CONFIG_OF
 static const struct of_device_id rzn1_dmamux_match[] = {
 	{ .compatible = "renesas,rzn1-dmamux" },
 	{}
 };
 MODULE_DEVICE_TABLE(of, rzn1_dmamux_match);
+#endif
 
 static struct platform_driver rzn1_dmamux_driver = {
 	.driver = {
 		.name = "renesas,rzn1-dmamux",
-		.of_match_table = rzn1_dmamux_match,
+		.of_match_table = of_match_ptr(rzn1_dmamux_match),
 	},
 	.probe	= rzn1_dmamux_probe,
 };
-- 
2.34.1