[L] Change in coreboot[main]: drivers/spi: add RPMC support

[Marshall Dawson (Code Review)]

Attention is currently required from: Felix Held.

Marshall Dawson has posted comments on this change by Felix Held. ( https://review.coreboot.org/c/coreboot/+/84837?usp=email )

Change subject: drivers/spi: add RPMC support
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Patch Set 9: Code-Review+2

(3 comments)

File src/drivers/spi/spi_flash_rpmc.c:

https://review.coreboot.org/c/coreboot/+/84837/comment/3bacf027_f699238b?usp... :
PS9, Line 250: 	memcpy(&buf[8], signature, SPI_RPMC_SIG_LEN);
Could consider using [4+SPI_RPMC_KEY_DATA_LEN], similar to line 218.

https://review.coreboot.org/c/coreboot/+/84837/comment/942f83c8_ef45e6c1?usp... :
PS9, Line 281: 	memcpy(&buf[8], signature, SPI_RPMC_SIG_LEN);
similar

https://review.coreboot.org/c/coreboot/+/84837/comment/eda8f64f_a180dee4?usp... :
PS9, Line 314: 	memcpy(&buf[16], signature, SPI_RPMC_SIG_LEN);
similar