Change in coreboot[master]: nb/intel/common: Create a common init_igd_opregion method

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Change subject: nb/intel/common: Create a common init_igd_opregion method
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Patch Set 2: Verified+1

Build Successful

https://qa.coreboot.org/job/coreboot-checkpatch/10103/ : SUCCESS

https://qa.coreboot.org/job/coreboot-gerrit/54374/ : SUCCESS