[RFC PATCH V4 2/6] riscv: errata: pgtable: Add custom Svpbmt supported for Allwinner D1

[Christoph Hellwig]

This is the wrong way around.  We need to design around the PBMT
definitions.  If we want to hack in support for completely broken SOCs
that intentionally violate the specification it should be done after
the fact, in a separate patch, using alternatives and clearly documenting
how broken these SOCs are.