PM: domains: Move the verification of in-params from genpd_add_device()

Commit f38d1a6d ("PM: domains: Allocate governor data dynamically
based on a genpd governor") started to use the in-parameters in
genpd_add_device(), without first doing a verification of them.

This isn't really a big problem, as most callers do a verification already.

Therefore, let's drop the verification from genpd_add_device() and make
sure all the callers take care of it instead.

Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Fixes: f38d1a6d ("PM: domains: Allocate governor data dynamically based on a genpd governor")
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>