firmware: ti_sci: Use the bitmap API to allocate bitmaps

Use devm_bitmap_zalloc() instead of hand-writing them.

It is less verbose and it improves the semantic.
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Nishanth Menon <nm@ti.com>
Link: https://lore.kernel.org/r/3ee11e9e83f7c1552d237f5c28f554319fcbbf1f.1657308216.git.christophe.jaillet@wanadoo.fr

drivers/firmware/ti_sci.c

@@ -3201,9 +3201,8 @@ devm_ti_sci_get_resource_sets(const struct ti_sci_handle *handle,
 
 		valid_set = true;
 		res_count = res->desc[i].num + res->desc[i].num_sec;
-		res->desc[i].res_map =
-			devm_kzalloc(dev, BITS_TO_LONGS(res_count) *
-				     sizeof(*res->desc[i].res_map), GFP_KERNEL);
+		res->desc[i].res_map = devm_bitmap_zalloc(dev, res_count,
+							  GFP_KERNEL);
 		if (!res->desc[i].res_map)
 			return ERR_PTR(-ENOMEM);
 	}