UBIFS: Fix dereferencing type-punned pointer compiler warning

Fix compiler warning

In file included from ubifs.h:2137:0,

                 from ubifs.c:26:

misc.h: In function 'ubifs_idx_key':
misc.h:263:26: warning: dereferencing type-punned pointer will break strict-aliasing rules

seen with gcc version 4.5.1 (Sourcery G++ Lite 2010.09-50).

No functional change.

---

This was found building 'omap3_pandora' with the above tool chain.

Note: Compiling the ubifs (make fs/ubifs) in a recent mainline kernel
(2.6.37-rc7) with the same tool chain doesn't give this warning. There seems to be no difference in the recent ubifs kernel sources regarding this piece of code (structs ubifs_idx_node, ubifs_branch and the function ubifs_idx_key in misc.h), though.
So I'm not sure why this warning is in U-Boot but not in the kernel. Different compiler options?

 fs/ubifs/misc.h |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

Index: u-boot.git/fs/ubifs/misc.h
===================================================================
@@ -260,7 +260,8 @@ struct ubifs_branch *ubifs_idx_branch(co
 static inline void *ubifs_idx_key(const struct ubifs_info *c,
 				  const struct ubifs_idx_node *idx)
 {
-	return (void *)((struct ubifs_branch *)idx->branches)->key;
+	const __u8 *branch = idx->branches;
+	return (void *)((struct ubifs_branch *)branch)->key;
 }
 
 /**

Applied to u-boot-ubi. Thanks.

Cheers,
Stefan

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