Change in coreboot[master]: lib/prog_loaders, soc/amd/: Make payload_preload use cbfs_preload

[Julius Werner (Code Review)]

Attention is currently required from: Jason Glenesk, Raul Rangel, Marshall Dawson, Rob Barnes, Karthik Ramasubramanian, Felix Held.
Julius Werner has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/58962 )

Change subject: lib/prog_loaders, soc/amd/: Make payload_preload use cbfs_preload
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Patch Set 1: Code-Review+2

(1 comment)

File src/lib/prog_loaders.c:

https://review.coreboot.org/c/coreboot/+/58962/comment/6f9035da_16324fa3 
PS1, Line 133: 		return;
nit: not sure why I didn't mention this first time this patch came around, but I think think this `return` could be a `dead_code()`. Platform code should not link in this function unless it actually intends to do preloading. Using dead_code() would enforce that at build time.