Duplicate sections in INF files are not merged

[RJohnsonPGH]

https://learn.microsoft.com/en-us/windows-hardware/drivers/install/general-syntax-rules-for-inf-files

If more than one section in an INF file has the same name, the system merges their entries and directives into a single section.

Currently, two sections with the same name will be parsed and returned as two separate sections. They should instead be merged. Duplicate keys should be a 'last entry wins'.