xfs: sanitize qh_lock wrappers

Get rid of various obsfucating wrappers for accessing the quota hash lock,
we only keep the accessors for accessing the mplist and freelist locks as
they encode a multi-level datastructure walk.  But make sure all of them
are defined in the same way as simple macros.

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