Change in coreboot[master]: vendorcode: Add VariableFormat.h

[Angel Pons (Code Review)]

Attention is currently required from: Patrick Rudolph.
Angel Pons has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/61959 )

Change subject: vendorcode: Add VariableFormat.h
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Patch Set 1: Code-Review+1

(1 comment)

Patchset:

PS1: 
Is there a way to avoid the UDK2017 dependency? If this is the only edk2 header needed to implement EFI variable store support in coreboot, I'd rather include it directly from the driver.