These cleanups came up as part of the discussion on the "riscv: Reduce
ARCH_KMALLOC_MINALIGN to 8" patch set, but that needs additional work
and thus will be delayed at least a cycle.

* b4-shazam-merge:
  riscv: mm: mark noncoherent_supported as __ro_after_init
  riscv: mm: mark CBO relate initialization funcs as __init
  riscv: errata: thead: only set cbom size & noncoherent during boot

Link: https://lore.kernel.org/linux-riscv/20230526165958.908-1-jszhang@kernel.org/
Link: https://lore.kernel.org/r/20230614165504.532-1-jszhang@kernel.org


Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>