genpt: Make GENERIC_PT invisible

genpt: Make GENERIC_PT invisible

There is no point in asking the user about the Generic Radix Page
Table API:
  - All IOMMU drivers that use this API already select GENERIC_PT when
    needed,
  - Most users probably do not know what to answer anyway.

Fixes: 7c5b184db7145fd4 ("genpt: Generic Page Table base API")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>