pinctrl: samsung: remove duplicated line

This patch removes duplicated line of samsung_pinctrl_register(),
because the number of pins is redundantly assigned twice.

Reviewed-by: Tomasz Figa <t.figa@samsung.com>
Acked-by: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>