mfd: bcm590xx: Drop of_match_ptr from of_device_id table

The driver can match only via the DT table so the table should be always
used and the of_match_ptr does not have any sense (this also allows ACPI
matching via PRP0001, even though it is not relevant here).  This fixes
compile warning (!CONFIG_OF on x86_64):

  drivers/mfd/bcm590xx.c:95:34: warning: ‘bcm590xx_of_match’ defined but not used [-Wunused-const-variable=]
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

drivers/mfd/bcm590xx.c

@@ -107,7 +107,7 @@ MODULE_DEVICE_TABLE(i2c, bcm590xx_i2c_id);
 static struct i2c_driver bcm590xx_i2c_driver = {
 	.driver = {
 		   .name = "bcm590xx",
-		   .of_match_table = of_match_ptr(bcm590xx_of_match),
+		   .of_match_table = bcm590xx_of_match,
 	},
 	.probe = bcm590xx_i2c_probe,
 	.id_table = bcm590xx_i2c_id,