xfs: fix the xfs_log_iovec i_addr type

By making this member a void pointer we can get rid of a lot of pointless
casts.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>

diff --git a/fs/xfs/xfs_log.h b/fs/xfs/xfs_log.h
index 04c78e6..5b72e9a 100644
--- a/fs/xfs/xfs_log.h
+++ b/fs/xfs/xfs_log.h
@@ -104,7 +104,7 @@
 #define XLOG_REG_TYPE_MAX		19
 
 typedef struct xfs_log_iovec {
-	xfs_caddr_t	i_addr;		/* beginning address of region */
+	void		*i_addr;	/* beginning address of region */
 	int		i_len;		/* length in bytes of region */
 	uint		i_type;		/* type of region */
 } xfs_log_iovec_t;