Change in coreboot[master]: arch/x86/postcar: Set up postcar MTRR in C code

[Subrata Banik (Code Review)]

Attention is currently required from: Jason Glenesk, Raul Rangel, Marshall Dawson, Arthur Heymans, Kyösti Mälkki, Aaron Durbin, Felix Held.
Subrata Banik has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/54299 )

Change subject: arch/x86/postcar: Set up postcar MTRR in C code
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Patch Set 11:

(3 comments)

File src/arch/x86/postcar.c:

https://review.coreboot.org/c/coreboot/+/54299/comment/f17092ea_6acd91b9 
PS11, Line 3: #include <cpu/x86/msr.h>
u can put this in order, rest looks good.

File src/cpu/x86/mtrr/earlymtrr.c:

https://review.coreboot.org/c/coreboot/+/54299/comment/04520047_26ab6207 
PS11, Line 126: 	for (int i = 0; i < ctx->max_var_mtrrs; i++) {
              : 		wrmsr(MTRR_PHYS_BASE(i), zero);
              : 		wrmsr(MTRR_PHYS_MASK(i), zero);
              : 	}
can't u use clear_all_var_mtrr() here ?

https://review.coreboot.org/c/coreboot/+/54299/comment/002e6140_6cd5ef72 
PS11, Line 131: 		wrmsr(MTRR_PHYS_BASE(i), ctx->mtrr[i].base);
              : 		wrmsr(MTRR_PHYS_MASK(i), ctx->mtrr[i].mask);
set_var_mtrr() may be ?