mm, vmalloc: use clamp() to simplify code

Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/vmalloc.c

@@ -1330,16 +1330,8 @@ static struct vm_struct *__get_vm_area_node(unsigned long size,
 	struct vm_struct *area;
 
 	BUG_ON(in_interrupt());
-	if (flags & VM_IOREMAP) {
-		int bit = fls(size);
-
-		if (bit > IOREMAP_MAX_ORDER)
-			bit = IOREMAP_MAX_ORDER;
-		else if (bit < PAGE_SHIFT)
-			bit = PAGE_SHIFT;
-
-		align = 1ul << bit;
-	}
+	if (flags & VM_IOREMAP)
+		align = 1ul << clamp(fls(size), PAGE_SHIFT, IOREMAP_MAX_ORDER);
 
 	size = PAGE_ALIGN(size);
 	if (unlikely(!size))