irqchip/gic-v2m: 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/20210618151657.65305-3-andriy.shevchenko@linux.intel.com

drivers/irqchip/irq-gic-v2m.c

@@ -269,7 +269,7 @@ static void gicv2m_teardown(void)
 
 	list_for_each_entry_safe(v2m, tmp, &v2m_nodes, entry) {
 		list_del(&v2m->entry);
-		kfree(v2m->bm);
+		bitmap_free(v2m->bm);
 		iounmap(v2m->base);
 		of_node_put(to_of_node(v2m->fwnode));
 		if (is_fwnode_irqchip(v2m->fwnode))
@@ -386,8 +386,7 @@ static int __init gicv2m_init_one(struct fwnode_handle *fwnode,
 			break;
 		}
 	}
-	v2m->bm = kcalloc(BITS_TO_LONGS(v2m->nr_spis), sizeof(long),
-			  GFP_KERNEL);
+	v2m->bm = bitmap_zalloc(v2m->nr_spis, GFP_KERNEL);
 	if (!v2m->bm) {
 		ret = -ENOMEM;
 		goto err_iounmap;