Change in coreboot[master]: vendor: mediatek: Add mediatek mt8192 dram initialization codes

[Xi Chen (Code Review)]

Attention is currently required from: Hung-Te Lin, Nico Huber, Martin Roth, Paul Menzel, Yu-Ping Wu.
Xi Chen has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/50294 )

Change subject: vendor: mediatek: Add mediatek mt8192 dram initialization codes
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Patch Set 13:

(1 comment)

File src/vendorcode/mediatek/mt8192/dram_init.c:

https://review.coreboot.org/c/coreboot/+/50294/comment/18cf4f68_549e86e2 
PS9, Line 59: void _start(void *config) __attribute__((section(".text.start")));
            : void _start(void *config)
            : {
            : 	dram_init(config);
            : }
            :
> I think we should remove this if you don't have a plan to build blob here.

Ack