perf/arm-cci: Use the bitmap API to allocate bitmaps

Use devm_bitmap_zalloc() instead of hand-writing it.
It is less verbose and it improves the semantic.

While at it, use bitmap_zero() instead of hand-writing it.
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://lore.kernel.org/r/fbde85a5e8ae99b10a2115d8ea1e69320a62947f.1657084786.git.christophe.jaillet@wanadoo.frSigned-off-by: Will Deacon <will@kernel.org>

drivers/perf/arm-cci.c

@@ -1261,7 +1261,7 @@ static int validate_group(struct perf_event *event)
 		 */
 		.used_mask = mask,
 	};
-	memset(mask, 0, BITS_TO_LONGS(cci_pmu->num_cntrs) * sizeof(unsigned long));
+	bitmap_zero(mask, cci_pmu->num_cntrs);
 
 	if (!validate_event(event->pmu, &fake_pmu, leader))
 		return -EINVAL;
@@ -1629,10 +1629,9 @@ static struct cci_pmu *cci_pmu_alloc(struct device *dev)
 					     GFP_KERNEL);
 	if (!cci_pmu->hw_events.events)
 		return ERR_PTR(-ENOMEM);
-	cci_pmu->hw_events.used_mask = devm_kcalloc(dev,
-						BITS_TO_LONGS(CCI_PMU_MAX_HW_CNTRS(model)),
-						sizeof(*cci_pmu->hw_events.used_mask),
-						GFP_KERNEL);
+	cci_pmu->hw_events.used_mask = devm_bitmap_zalloc(dev,
+							  CCI_PMU_MAX_HW_CNTRS(model),
+							  GFP_KERNEL);
 	if (!cci_pmu->hw_events.used_mask)
 		return ERR_PTR(-ENOMEM);