irqchip/partitions: Switch to bitmap_zalloc()

Switch to bitmap_zalloc() to show clearly what we are allocating.
Besides that it returns pointer of bitmap type instead of opaque void *.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20210618151657.65305-1-andriy.shevchenko@linux.intel.com

drivers/irqchip/irq-partition-percpu.c

@@ -215,8 +215,7 @@ struct partition_desc *partition_create_desc(struct fwnode_handle *fwnode,
 		goto out;
 	desc->domain = d;
 
-	desc->bitmap = kcalloc(BITS_TO_LONGS(nr_parts), sizeof(long),
-			       GFP_KERNEL);
+	desc->bitmap = bitmap_zalloc(nr_parts, GFP_KERNEL);
 	if (WARN_ON(!desc->bitmap))
 		goto out;