Add Helium 7 support for package builds. - During operation, if last.major.helium.version is detected as 7.0 then it will use new sbsinput mechanism. - Restore sf-postbuild dependency on sf-build-noprep target

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