mmc: tegra: fix inconsistent IS_ERR and PTR_ERR

Fix inconsistent IS_ERR and PTR_ERR in tegra_sdhci_init_pinctrl_info,
the proper pointer to be passed as argument is 'pinctrl_state_1v8'

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Reviewed-by: Aapo Vienamo <aapo.vienamo@iki.fi>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>