share_pool: Fix compilation error of do_mm_populate()

ascend inclusion
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I4EUVI
CVE: NA

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do_mm_populate() should return an error number.
Signed-off-by: NTang Yizhou <tangyizhou@huawei.com>
Reviewed-by: NKefeng Wang <wangkefeng.wang@huawei.com>
Reviewed-by: NDing Tianhong <dingtianhong@huawei.com>
Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>
Reviewed-by: NWeilong Chen <chenweilong@huawei.com>
Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>

include/linux/mm.h

@@ -2448,9 +2448,10 @@ extern int do_mm_populate(struct mm_struct *mm, unsigned long addr, unsigned lon
 			  int ignore_errors);
 #else
 static inline void mm_populate(unsigned long addr, unsigned long len) {}
-int do_mm_populate(struct mm_struct *mm, unsigned long addr, unsigned long len,
-		   int ignore_errors)
+static inline int do_mm_populate(struct mm_struct *mm, unsigned long addr,
+				 unsigned long len, int ignore_errors)
 {
+	return -EPERM;
 }
 #endif