idpf trailing whitespace in spec file

[JonKohler]

small "nit" level issue, in the idpf spec file, there is a handful of trailing whitespace @etantilov

Normally I wouldn't care, but this does get flagged when rebuilding in our specific incantation of a code review tool :)

Line 27 as an example:
https://github.com/intel/ethernet-linux-idpf/blame/v0.0.766/idpf.spec#L27C47-L27C47

[etantilov]

Thanks for pointing that out. I will clean them up.