malloc: no longer need to round mempool's max_sz

Since commit 465b2cf31b this value is rounded at compile time instead.

Signed-off-by: Nicolas Pitre <npitre@baylibre.com>
diff --git a/lib/libc/minimal/source/stdlib/malloc.c b/lib/libc/minimal/source/stdlib/malloc.c
index ae8efbc..ce7536f 100644
--- a/lib/libc/minimal/source/stdlib/malloc.c
+++ b/lib/libc/minimal/source/stdlib/malloc.c
@@ -105,7 +105,7 @@
 	/* Determine size of previously allocated block by its level.
 	 * Most likely a bit larger than the original allocation
 	 */
-	block_size = _ALIGN4(blk->pool->base.max_sz);
+	block_size = blk->pool->base.max_sz;
 	for (int i = 1; i <= blk->level; i++) {
 		block_size = _ALIGN4(block_size / 4);
 	}