[resend PATCH v2 01/33] device-dax: rename 'dax_dev' to 'dev_dax'

In preparation for introducing a struct dax_device type to the kernel global type namespace, rename dax_dev to dev_dax. A 'dax_device' instance will be a generic device-driver object for any provider of dax functionality. A 'dev_dax' object is a device-dax-driver local / internal instance. Signed-

[PATCH v2 01/33] device-dax: rename 'dax_dev' to 'dev_dax'

In preparation for introducing a struct dax_device type to the kernel global type namespace, rename dax_dev to dev_dax. A 'dax_device' instance will be a generic device-driver object for any provider of dax functionality. A 'dev_dax' object is a device-dax-driver local / internal instance. Signed-