parasite: remove excessive header deps from parasite.h and friends

The task is not complete - this is just a part of what have to be done. I.e.
looks like a lot of excessive deps can be fixed.

Signed-off-by: Stanislav Kinsbursky <skinsbursky@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>