drm/amd/pm: use kmemdup() rather than kmalloc+memcpy

Issue identified with Coccinelle.
Signed-off-by: Alex Dewar <alex.dewar90@gmail.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/pm/powerplay/hwmgr/vega20_processpptables.c

@@ -890,14 +890,12 @@ static int init_powerplay_table_information(
 				power_saving_clock_count);
 	}
 
-	pptable_information->smc_pptable = kmalloc(sizeof(PPTable_t), GFP_KERNEL);
+	pptable_information->smc_pptable = kmemdup(&(powerplay_table->smcPPTable),
+						   sizeof(PPTable_t),
+						   GFP_KERNEL);
 	if (pptable_information->smc_pptable == NULL)
 		return -ENOMEM;
 
-	memcpy(pptable_information->smc_pptable,
-			&(powerplay_table->smcPPTable),
-			sizeof(PPTable_t));
-
 
 	result = append_vbios_pptable(hwmgr, (pptable_information->smc_pptable));
 	if (result)