[S] Change in coreboot[master]: soc/mediatek/mt8188: enable mfgpll properly and fix SPMI muxes

[Yidi Lin (Code Review)]

Attention is currently required from: Hung-Te Lin, Rex-BC Chen, Yu-Ping Wu.

Yidi Lin has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/67355 )

Change subject: soc/mediatek/mt8188: enable mfgpll properly and fix SPMI muxes
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Patch Set 4:

(2 comments)

Commit Message:

https://review.coreboot.org/c/coreboot/+/67355/comment/760c830d_7c144d7b 
PS4, Line 7: enable
Enable

File src/soc/mediatek/mt8188/pll.c:

https://review.coreboot.org/c/coreboot/+/67355/comment/944afe19_ef7e100e 
PS4, Line 524: /* disable mfg_ck_en[20], enable mfg_opp_ck_en[2]  */
             : 	clrbits32(&mtk_apmixed->mfgpll_con0, 0x1 << 20);
             : 	clrsetbits32(&mtk_apmixed->mfgpll_con0, 0x1 << 2, 0x1 << 2);
clrsetbits32(&mtk_apmixed->mfgpll_con0, BIT(20), BIT(2));