Add the device to dma_buf's attachments list; optionally, calls
attach of dma_buf_ops to allow device-specific attach functionality
struct dma_buf_attachment * dma_buf_attach (
|struct dma_buf * dmabuf, |
| ||struct device * dev|
[in] buffer to attach device to.
[in] device to be attached.
Returns struct dma_buf_attachment * for this attachment; returns ERR_PTR on