soc: renesas: Make ARCH_R9A07G043 depend on required options

Randy reported a randconfig build issue against linux-next:

    WARNING: unmet direct dependencies detected for ERRATA_ANDES
      Depends on [n]: RISCV_ALTERNATIVE [=n] && RISCV_SBI [=y]
      Selected by [y]:
      - ARCH_R9A07G043 [=y] && SOC_RENESAS [=y] && RISCV [=y] && NONPORTABLE [=y] && RISCV_SBI [=y]

    ../arch/riscv/errata/andes/errata.c:59:54: warning: 'struct alt_entry' declared inside parameter list will not be visible outside of this definition or declaration
       59 | void __init_or_module andes_errata_patch_func(struct alt_entry *begin, struct alt_entry *end,

On RISC-V, alternatives are not usable in XIP kernels, which this
randconfig happened to select.  Rather than add a check for whether
alternatives are available before selecting the ERRATA_ANDES config
option, rework the R9A07G043 Kconfig entry to depend on the
configuration options required to support its non-standard cache
coherency implementation.

Without these options enabled, the SoC is effectively non-functional to
begin with, so there's an extra benefit in preventing the creation of
non-functional kernels.

The "if RISCV_DMA_NONCOHERENT" can be dropped, as ERRATA_ANDES_CMO will
select it.

Reported-by: Randy Dunlap <rdunlap@infradead.org>
Closes: https://lore.kernel.org/all/09a6b0f0-76a1-45e3-ab52-329c47393d1d@infradead.org/


Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20231012-pouch-parkway-7d26c04b3300@spud


Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>