Add haveCpuLocalForces flag to DomainLifetimeWorkload

Add haveCpuLocalForces flag to DomainLifetimeWorkload

The flag haveCpuLocalForces is moved to DomainLifetimeWorkload.
The name and meaning is also slightly changed, haveCpuLocalForceWork
now now indicates whether any forces in the local domain are computed
on the CPU.
Consequently, the currently redundant PME f reduction conditional has
been removed from the haveCpuLocalForceWork initialization. The
relationship between local force work and existence of local forces on
the CPU however needs to be clarified in relationship to #3160 and how
the PP-PME direct communication is improved/simplified.

Change-Id: Idaed4da41bf5b72435c47bab8aeb7130b36b03c7