Platform Build - Added 'sf-postbuild' onto deps for 'sf-build-noprep' as although it isn't the best place to have it, it's the same as the deps for the version in 'common' and is needed for the external Hudson jobs.

^SHOWSTOPPER RAISED:	critical
^ERROR:	major
^WARNING: .+ CANNOT BE FOUND IN THE SYSTEM PATH	ignore
^WARNING:	minor