xfs: move xfs_get_extsz_hint() and kill xfs_rw.h

The only thing left in xfs_rw.h is a function prototype for an inode
function.  Move that to xfs_inode.h, and kill xfs_rw.h.

Also move the function implementing the prototype from xfs_rw.c to
xfs_inode.c so we only have one function left in xfs_rw.c

Signed-off-by: Dave Chinner <[email protected]>
Reviewed-by: Mark Tinguely <[email protected]>
Reviewed-by: Christoph Hellwig <[email protected]>
Signed-off-by: Ben Myers <[email protected]>
16 files changed