Consolidate vme_bridge structure setup that every bridge was required
to do itself. This came about because .irq_mtx is only used within the
VME core, but was required to be setup externally.
This returns the structure passed in to support shorthand like this:
bridge = vme_init_bridge(&priv->bridge);
Signed-off-by: Aaron Sierra <firstname.lastname@example.org>
Acked-by: Martyn Welch <email@example.com>
Signed-off-by: Greg Kroah-Hartman <firstname.lastname@example.org>