Change in coreboot[master]: soc/intel/fast_spi: Use `need_restore_mtrr()` to clear temp MTRR

[Subrata Banik (Code Review)]

Attention is currently required from: Tim Wawrzynczak, Arthur Heymans, Nick Vaccaro, Eric Lai.
Subrata Banik has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/63492 )

Change subject: soc/intel/fast_spi: Use `need_restore_mtrr()` to clear temp MTRR
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Patch Set 2:

(1 comment)

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

https://review.coreboot.org/c/coreboot/+/63492/comment/5763e43e_dce8a62a 
PS1, Line 52: /* Need to restore mtrr later using remove_temp_solution. */
            : 	if (ENV_RAMSTAGE)
            : 		need_restore_mtrr();
> Ack

@Arthur, can you please take a look into this Temp solution, till we figure out how to manage ramstage Temp MTRR solution in better way using CB:63550 or CB:63555.