pinctrl: st: Use ARRAY_SIZE for STiH415 data

This patch completes the one that used ARRAY_SIZE for STiH407 and STiH416
for setting ninput_delays and noutput_delays fields.

Signed-off-by: Maxime Coquelin <maxime.coquelin@st.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>