[PATCH] f2fs: fix compile warning

[Chao Yu]

This patch fixes below compile warning reported by LKP
(kernel test robot)

cppcheck warnings: (new ones prefixed by >>)

>> fs/f2fs/file.c:761:9: warning: Identical condition 'err', second condition 
>> is always false [identicalConditionAfterEarlyExit]
    return err;
           ^
   fs/f2fs/file.c:753:6: note: first condition
    if (err)
        ^
   fs/f2fs/file.c:761:9: note: second condition
    return err;

Reported-by: kernel test robot <l...@intel.com>
Signed-off-by: Chao Yu <yuch...@huawei.com>
---
 fs/f2fs/file.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index 8a422400e824..f16120352f0c 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -753,11 +753,14 @@ int f2fs_truncate_blocks(struct inode *inode, u64 from, 
bool lock)
                return err;
 
 #ifdef CONFIG_F2FS_FS_COMPRESSION
-       if (from != free_from)
+       if (from != free_from) {
                err = f2fs_truncate_partial_cluster(inode, from, lock);
+               if (err)
+                       return err;
+       }
 #endif
 
-       return err;
+       return 0;
 }
 
 int f2fs_truncate(struct inode *inode)
-- 
2.26.2