drivers: sh: Leave disabling of unused PM domains to genpd

drivers: sh: Leave disabling of unused PM domains to genpd

Since genpd at late init, will try to disable unused PM domains we
don't need to do it from here as well.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Simon Horman <horms+renesas@verge.net.au>
Reviewed-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
(cherry picked from commit f1bf45c70ffdcf048d046da4ad4611315f1a15bf)
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>