[PATCH] btrfs: suppress a build warning on building 32bit kernel

[Satoru Takeuchi <takeuchi_satoru@jp.fujitsu.com>]

From: Satoru Takeuchi <takeuchi_satoru@jp.fujitsu.com>

Suppress the following warning displayed on building 32bit (i686) kernel.

===============================================================================
...
   CC [M]  fs/btrfs/extent_io.o
fs/btrfs/extent_io.c: In function ‘btrfs_free_io_failure_record’:
fs/btrfs/extent_io.c:2193:13: warning: cast to pointer from integer of
different size [-Wint-to-pointer-cast]
    failrec = (struct io_failure_record *)state->private;
...
===============================================================================

Signed-off-by: Satoru Takeuchi <takeuchi_satoru@jp.fujitsu.com>
Reported-by: Chris Murphy <chris@colorremedies.com>

---
  fs/btrfs/extent_io.c | 2 +-
  1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 4ebabd2..790dbae 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -2190,7 +2190,7 @@ void btrfs_free_io_failure_record(struct inode *inode, u64 start, u64 end)
  
  		next = next_state(state);
  
-		failrec = (struct io_failure_record *)state->private;
+		failrec = (struct io_failure_record *)(unsigned long)state->private;
  		free_extent_state(state);
  		kfree(failrec);
  
-- 
1.8.3.1