i2c: at91: Use of_match_ptr() macro

This eliminates having an #ifdef returning NULL for the case
when OF is disabled.

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Acked-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
diff --git a/drivers/i2c/busses/i2c-at91.c b/drivers/i2c/busses/i2c-at91.c
index 75195e3..23a1c44 100644
--- a/drivers/i2c/busses/i2c-at91.c
+++ b/drivers/i2c/busses/i2c-at91.c
@@ -603,8 +603,6 @@
 	}
 };
 MODULE_DEVICE_TABLE(of, atmel_twi_dt_ids);
-#else
-#define atmel_twi_dt_ids NULL
 #endif
 
 static bool filter(struct dma_chan *chan, void *slave)
@@ -828,7 +826,7 @@
 	.driver		= {
 		.name	= "at91_i2c",
 		.owner	= THIS_MODULE,
-		.of_match_table = atmel_twi_dt_ids,
+		.of_match_table = of_match_ptr(atmel_twi_dt_ids),
 		.pm	= at91_twi_pm_ops,
 	},
 };