riscv: only select DMA_DIRECT_REMAP from RISCV_ISA_ZICBOM and ERRATA_THEAD_PBMT

riscv: only select DMA_DIRECT_REMAP from RISCV_ISA_ZICBOM and ERRATA_THEAD_PBMT

RISCV_DMA_NONCOHERENT is also used for whacky non-standard
non-coherent ops that use different hooks in dma-direct.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Tested-by: Samuel Holland <samuel.holland@sifive.com>
Link: https://lore.kernel.org/r/20231018052654.50074-3-hch@lst.de
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>