vdpa: fix typos in the comments for __vdpa_alloc_device()

Fix two typos in the comments for __vdpa_alloc_device().

Signed-off-by: Jason Wang <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Michael S. Tsirkin <[e-mail]>

drivers/vdpa/vdpa.c

···
  * @config: the bus operations that is supported by this device
  * @size: size of the parent structure that contains private data
  *
- * Drvier should use vdap_alloc_device() wrapper macro instead of
+ * Driver should use vdpa_alloc_device() wrapper macro instead of
  * using this directly.
  *
  * Returns an error when parent/config/dma_dev is not set or fail to get