vfio: Move iova_bitmap into iommufd

Both VFIO and IOMMUFD will need iova bitmap for storing dirties and walking
the user bitmaps, so move to the common dependency into IOMMUFD.  In doing
so, create the symbol IOMMUFD_DRIVER which designates the builtin code that
will be used by drivers when selected. Today this means MLX5_VFIO_PCI and
PDS_VFIO_PCI. IOMMU drivers will do the same (in future patches) when
supporting dirty tracking and select IOMMUFD_DRIVER accordingly.

Given that the symbol maybe be disabled, add header definitions in
iova_bitmap.h for when IOMMUFD_DRIVER=n

Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Joao Martins <[email protected]>
Reviewed-by: Jason Gunthorpe <[email protected]>
Reviewed-by: Brett Creeley <[email protected]>
Reviewed-by: Kevin Tian <[email protected]>
Reviewed-by: Alex Williamson <[email protected]>
Signed-off-by: Jason Gunthorpe <[email protected]>

0 files changed, 0 insertions, 0 deletions