mm/madvise.c: fix return value of madvise_hwpoison()

The return value outside for loop is always zero which means
madvise_hwpoison return success, however, this is not truth for
soft_offline_page w/ failure return value.
Signed-off-by: NWanpeng Li <liwanp@linux.vnet.ibm.com>
Reviewed-by: NNaoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Andi Kleen <andi@firstfloor.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

mm/madvise.c

@@ -361,7 +361,7 @@ static int madvise_hwpoison(int bhv, unsigned long start, unsigned long end)
 				page_to_pfn(p), start);
 			ret = soft_offline_page(p, MF_COUNT_INCREASED);
 			if (ret)
-				break;
+				return ret;
 			continue;
 		}
 		pr_info("Injecting memory failure for page %#lx at %#lx\n",