dmaengine: mv_xor: 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/dma/mv_xor.c:1281:34: warning:
        ‘mv_xor_dt_ids’ defined but not used [-Wunused-const-variable=]
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Link: https://lore.kernel.org/r/20201120162303.482126-3-krzk@kernel.orgSigned-off-by: Vinod Koul <vkoul@kernel.org>

drivers/dma/mv_xor.c

@@ -1455,7 +1455,7 @@ static struct platform_driver mv_xor_driver = {
 	.resume         = mv_xor_resume,
 	.driver		= {
 		.name	        = MV_XOR_NAME,
-		.of_match_table = of_match_ptr(mv_xor_dt_ids),
+		.of_match_table = mv_xor_dt_ids,
 	},
 };