drivers: CCI: fix the error handle in cci_pmu_probe()

This patch fix the error handle of function cci_pmu_probe():
- using IS_ERR() instead of NULL test for the return value of
  devm_ioremap_resource() since it nerver return NULL.
- remove kfree() for devm_kzalloc allocated memory
- remove dev_warn() since devm_ioremap_resource() has error message
  already.

Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Will Deacon <will.deacon@arm.com>

drivers/bus/arm-cci.c

@@ -565,18 +565,9 @@ static int cci_pmu_probe(struct platform_device *pdev)
 		return -ENOMEM;
 
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	if (!res) {
-		dev_warn(&pdev->dev, "Failed to get mem resource\n");
-		ret = -EINVAL;
-		goto memalloc_err;
-	};
-
 	pmu->base = devm_ioremap_resource(&pdev->dev, res);
-	if (!pmu->base) {
-		dev_warn(&pdev->dev, "Failed to ioremap\n");
-		ret = -ENOMEM;
-		goto memalloc_err;
-	}
+	if (IS_ERR(pmu->base))
+		return -ENOMEM;
 
 	/*
 	 * CCI PMU has 5 overflow signals - one per counter; but some may be tied
@@ -601,38 +592,28 @@ static int cci_pmu_probe(struct platform_device *pdev)
 	if (i < CCI_PMU_MAX_HW_EVENTS) {
 		dev_warn(&pdev->dev, "In-correct number of interrupts: %d, should be %d\n",
 			i, CCI_PMU_MAX_HW_EVENTS);
-		ret = -EINVAL;
-		goto memalloc_err;
+		return -EINVAL;
 	}
 
 	pmu->port_ranges = port_range_by_rev();
 	if (!pmu->port_ranges) {
 		dev_warn(&pdev->dev, "CCI PMU version not supported\n");
-		ret = -EINVAL;
-		goto memalloc_err;
+		return -EINVAL;
 	}
 
 	pmu->cci_pmu = devm_kzalloc(&pdev->dev, sizeof(*(pmu->cci_pmu)), GFP_KERNEL);
-	if (!pmu->cci_pmu) {
-		ret = -ENOMEM;
-		goto memalloc_err;
-	}
+	if (!pmu->cci_pmu)
+		return -ENOMEM;
 
 	pmu->hw_events.events = pmu->events;
 	pmu->hw_events.used_mask = pmu->used_mask;
 	raw_spin_lock_init(&pmu->hw_events.pmu_lock);
 
 	ret = cci_pmu_init(pmu->cci_pmu, pdev);
 	if (ret)
-		goto pmuinit_err;
+		return ret;
 
 	return 0;
-
-pmuinit_err:
-	kfree(pmu->cci_pmu);
-memalloc_err:
-	kfree(pmu);
-	return ret;
 }
 
 static int cci_platform_probe(struct platform_device *pdev)