[S] Change in coreboot[main]: riscv/opensbi: make the opensbi payload a flat binary

[Arthur Heymans (Code Review)]

Attention is currently required from: Arthur Heymans, Jonathan Neuschäfer, Maximilian Brune, Philipp Hug, ron minnich.

Arthur Heymans has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/81632?usp=email )

Change subject: riscv/opensbi: make the opensbi payload a flat binary
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Patch Set 4:

(2 comments)

File src/arch/riscv/Makefile.mk:

https://review.coreboot.org/c/coreboot/+/81632/comment/ac0f96e4_eb3d3874 :
PS4, Line 178: $(OPENSBI_CBFS)-compression := non
is it executed in place? or why not compress?

File src/mainboard/emulation/qemu-riscv/memlayout.ld:

https://review.coreboot.org/c/coreboot/+/81632/comment/b12468ce_24018e09 :
PS4, Line 9: #define ROMSTAGESIZE 0
Why this change?