Merge branch 'mailbox-for-next' of git://git.linaro.org/landing-teams/working/fujitsu/integration

Pull mailbox updates from Jassi Brar.

* 'mailbox-for-next' of git://git.linaro.org/landing-teams/working/fujitsu/integration:
  mailbox/bcm2835: Fix mailbox full detection.
  dt: mailbox: Remove 'mbox-names property is discouraged' message from binding
  mailbox: Add ability for clients to request channels by name
  mailbox: Enable BCM2835 mailbox support
  dt/bindings: Add binding for the BCM2835 mailbox driver
  mailbox: Fix up error handling in mbox_request_channel()
  mailbox: Make mbox_chan_ops const
  mailbox: altera: Add dependency on HAS_IOMEM