Change in coreboot[master]: soc/intel/common: Implement IOC driver

[Subrata Banik (Code Review)]

Attention is currently required from: Jamie Ryu, Wonkyu Kim, Ethan Tsao, Ravishankar Sarawadi, Paul Menzel, Tim Wawrzynczak, Angel Pons, Nick Vaccaro.
Subrata Banik has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/63198 )

Change subject: soc/intel/common: Implement IOC driver
......................................................................

Patch Set 17:

(3 comments)

File src/soc/intel/common/block/ioc/ioc.c:

https://review.coreboot.org/c/coreboot/+/63198/comment/38ef7848_1a61e123 
PS17, Line 12: get_mchbar
I would have written this logic as below

1. Read and check if MCH BAR is already assigned and Enable bit is set. Then return MCHBAR
2. Else, call below function to set the MCH BAR and return the same.
    sa_set_mch_bar(soc_fixed_mch_resources,
    	       ARRAY_SIZE(soc_fixed_mch_resources));

In either case, I would have move this into systemagent_early.c file as well.

https://review.coreboot.org/c/coreboot/+/63198/comment/f0379457_8d848a40 
PS17, Line 16: if(
if (

https://review.coreboot.org/c/coreboot/+/63198/comment/1373b143_f75692ce 
PS17, Line 25: void ioc_reg_write32(uint32_t offset, uint32_t value)
             : {
             : 	uint32_t mchbar = get_mchbar();
             : 
             : 	if(mchbar)
             : 		write32p(MCH_BASE_ADDRESS + offset, value);
             : }
void ioc_reg_write32(uint32_t offset, uint32_t value)
{
      uint32_t mchbar = get_mchbar();

write32p(mchbar + offset, value);
}