Change in coreboot[master]: drivers/intel/fsp2_0: Allow `mp_startup_all_cpus()` to run serially

[Felix Held (Code Review)]

Attention is currently required from: Subrata Banik.
Felix Held has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/57343 )

Change subject: drivers/intel/fsp2_0: Allow `mp_startup_all_cpus()` to run serially
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Patch Set 7:

(1 comment)

File src/drivers/intel/fsp2_0/ppi/mp_service_ppi.c:

https://review.coreboot.org/c/coreboot/+/57343/comment/933f54e6_1a646578 
PS7, Line 99: != CB_SUCCESS
after CB:58494 mp_run_on_aps and mp_run_on_all_aps return enum cb_err type, so it should be checked against != CB_SUCCESS instead of implicitly checked against != 0. since CB_SUCCESS is defined as 0, this won't break functionality, but i still would like you to check against the enum value