Change in coreboot[master]: libpayload: Add boot_device_read() function

[Jakub Czapiga (Code Review)]

Attention is currently required from: Julius Werner.
Jakub Czapiga has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/59492 )

Change subject: libpayload: Add boot_device_read() function
......................................................................

Patch Set 4:

(1 comment)

File payloads/libpayload/libc/boot_device.c:

https://review.coreboot.org/c/coreboot/+/59492/comment/b91aab2c_c8fba1a9 
PS1, Line 8: __attribute__((weak)) ssize_t libpayload_boot_device_read(void *buf, size_t offset, size_t size)
> I'm saying this should be implemented similarly to arch/x86/rom_media. […]

Done