[M] Change in coreboot[main]: mb/emulation/qemu-riscv: Change to -bios option

[Maximilian Brune (Code Review)]

Attention is currently required from: Arthur Heymans, Philipp Hug.

Maximilian Brune has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/80746?usp=email )

Change subject: mb/emulation/qemu-riscv: Change to -bios option
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Patch Set 5:

(1 comment)

File src/mainboard/emulation/qemu-riscv/cbmem.c:

https://review.coreboot.org/c/coreboot/+/80746/comment/2838cc8e_8bfca49a :
PS5, Line 10: 	return (uintptr_t)_dram + CONFIG_DRAM_SIZE_MB * MiB;
> Can use probing here instead of hard-coding

If you rebase CB:36486 on top of upstream main, then I could rebase on top of that and remove the hard code stuff.