pinctrl: renesas: rzg2l: Acquire lock in rzg2l_pinctrl_pm_setup_pfc()

To keep consistency with rzg2l_pinctrl_set_pfc_mode(), acquire the lock
in rzg2l_pinctrl_pm_setup_pfc() during PFC setup.

Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Tested-by: Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com> # on RZ/G3S
Link: https://lore.kernel.org/r/20240530173857.164073-15-prabhakar.mahadev-lad.rj@bp.renesas.com


Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>