[S] Change in coreboot[main]: arch/riscv: add Kconfig variable RISCV_SOC_HAS_MENVCFG

[Nico Huber (Code Review)]

Attention is currently required from: Maximilian Brune, Patrick Georgi, Philipp Hug, ron minnich.

Nico Huber has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/81410?usp=email )

The change is no longer submittable: All-Comments-Resolved is unsatisfied now.

Change subject: arch/riscv: add Kconfig variable RISCV_SOC_HAS_MENVCFG
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Patch Set 5: Code-Review+1

(1 comment)

File src/arch/riscv/Kconfig:

https://review.coreboot.org/c/coreboot/+/81410/comment/a7f59a98_03ccbb83 :
PS5, Line 120: 	depends on (!SOC_SIFIVE_FU540 && !SOC_SIFIVE_FU740)
Wouldn't it be better to handle this locally, e.g. in `soc/sifive/fu540/Kconfig`
```
config RISCV_SOC_HAS_MENVCFG
        default n
```

Even if we know that there won't be more cases, listing special cases in common
code is rather discouraged and we wouldn't want such a pattern to spread.