[FREELDR]: Report the correct number of BIOS (hard) disk drives detected, that is, without any possible extra boot drive that went enumerated afterwards.
This fixes the list of disks enumerated in HKEY_LOCAL_MACHINE\HARDWARE\DESCRIPTION\System\MultifunctionAdapter\0\DiskController\0\DiskPeripheral\
and we now behave in this regards similarly to Windows 2003 & co.
I thank Lesan Ilie for reporting & testing, and Serge Gautherie and Peter Hater for reviewing.
This fixes a bug introduced in commit r59079.
CORE-13131
svn path=/trunk/; revision=74515