[FREELDR] Load the Firmware Errata file specified in the registry. (#1951)

[FREELDR] Load the Firmware Errata file specified in the registry. (#1951)

On Windows <= 2003 (and current ReactOS), this is the "InfName" value
in the "HKEY_LOCAL_MACHINE\CurrentControlSet\Control\BiosInfo\" key.
(The default file name found there is 'biosinfo.inf'.)

On Vista+, this is the "InfName" value in the
"HKEY_LOCAL_MACHINE\CurrentControlSet\Control\Errata\" key.
(The default file name found there is 'errata.inf'.)

For 1st-stage setup, the file is specified in the "InfName" value of
the "BiosInfo" section in the TXTSETUP.SIF file.

Co-authored-by: Hermès Bélusca-Maïto <hermes.belusca-maito@reactos.org>