[S] Change in coreboot[main]: Support smmstore in RW_LEGACY

[Felix Held (Code Review)]

Attention is currently required from: Vladimir Serbinenko.

Felix Held has posted comments on this change by Vladimir Serbinenko. ( https://review.coreboot.org/c/coreboot/+/81507?usp=email )

Change subject: Support smmstore in RW_LEGACY
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Patch Set 3:

(1 comment)

File src/drivers/smmstore/store.c:

https://review.coreboot.org/c/coreboot/+/81507/comment/5e205d6b_3af519c7?usp... :
PS3, Line 60: 	    && cbfs_lookup(&rw_legacy_rdev, "smmstore.bin", &mdata, &data_offset, NULL) == 0) {
it seems that this new code isn't checking the alignment and size requirements. the smmstore in flash needs to start right on the beginning of an erase block and needs to end right at the end of an erase block so that we can be sure that doing an erase to the smmstore doesn't clobber anything outside of it