mm/hmm.c: remove unneeded local variable ret

The local variable ret is always 0. Remove it to make code more tight.

Link: https://lkml.kernel.org/r/20220125124833.39718-1-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Author: MiaoheLin

mm/hmm.c

@@ -417,7 +417,6 @@ static int hmm_vma_walk_pud(pud_t *pudp, unsigned long start, unsigned long end,
 	struct hmm_range *range = hmm_vma_walk->range;
 	unsigned long addr = start;
 	pud_t pud;
-	int ret = 0;
 	spinlock_t *ptl = pud_trans_huge_lock(pudp, walk->vma);
 
 	if (!ptl)
@@ -466,7 +465,7 @@ static int hmm_vma_walk_pud(pud_t *pudp, unsigned long start, unsigned long end,
 
 out_unlock:
 	spin_unlock(ptl);
-	return ret;
+	return 0;
 }
 #else
 #define hmm_vma_walk_pud	NULL