Change in coreboot[master]: soc/amd/cezanne: Add root_complex

[Angel Pons (Code Review)]

Attention is currently required from: Jason Glenesk, Raul Rangel, Martin Roth, Marshall Dawson, Felix Held.
Angel Pons has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/50339 )

Change subject: soc/amd/cezanne: Add root_complex
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Patch Set 1:

(3 comments)

File src/soc/amd/cezanne/root_complex.c:

https://review.coreboot.org/c/coreboot/+/50339/comment/4aa97bf0_e6e74c44 
PS1, Line 23: reserved_dram_end
To avoid having so much empty space on the left margin, how about moving this to the right side?

https://review.coreboot.org/c/coreboot/+/50339/comment/ea8d2c39_5b5566ab 
PS1, Line 88: 1MB
nit: MiB

https://review.coreboot.org/c/coreboot/+/50339/comment/8206460c_2732ae3b 
PS1, Line 97: *
nit: remove this `*` to comply with the coding style