Description of problem:
Parted now correctly sets partition type to 0x41 when you set the flag
PARTITION_PREP, we need to expose this within pyparted so that anaconda can not
have to use sfdisk...
Probably want to check for other flags too.
Added the new ones to pyparted-1.7.2-1.fc6, so you now have PARTITION_PREP (in
addition to PARTITION_HPSERVICE, PARTITION_PALO, and PARTITION_MSFT_RESERVED).