simplify the mdev interface

[Christoph Hellwig]

Hi all,

this series signigicantly simplies the mdev driver interface by following
the patterns for device model interaction used elsewhere in the kernel.

Diffstat:
 Documentation/driver-api/vfio-mediated-device.rst |   16 -
 Documentation/s390/vfio-ap.rst                    |    2 
 Documentation/s390/vfio-ccw.rst                   |    2 
 drivers/gpu/drm/i915/gvt/gvt.h                    |    1 
 drivers/gpu/drm/i915/gvt/kvmgt.c                  |  116 ++++----------
 drivers/gpu/drm/i915/i915_drv.h                   |    2 
 drivers/s390/cio/cio.h                            |    3 
 drivers/s390/cio/vfio_ccw_ops.c                   |   32 +--
 drivers/s390/crypto/vfio_ap_ops.c                 |   25 +--
 drivers/s390/crypto/vfio_ap_private.h             |    2 
 drivers/vfio/mdev/mdev_core.c                     |  181 ++++------------------
 drivers/vfio/mdev/mdev_driver.c                   |    1 
 drivers/vfio/mdev/mdev_private.h                  |   38 ----
 drivers/vfio/mdev/mdev_sysfs.c                    |  145 ++---------------
 include/linux/mdev.h                              |   40 +++-
 samples/vfio-mdev/mbochs.c                        |   69 ++++----
 samples/vfio-mdev/mdpy.c                          |   61 +++----
 samples/vfio-mdev/mtty.c                          |   77 +++++----
 18 files changed, 258 insertions(+), 555 deletions(-)