soc: renesas: rcar-sysc: Eliminate local variable gov

As of commit 980532a5

 ("soc: renesas: rcar-sysc: Use
GENPD_FLAG_ALWAYS_ON"), the local variable "gov" is assigned just once,
so it can be eliminated.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>