plat/nvidia: tegra: Rename SMC API

Renamed SMC API from "plat_smccc_feature_available" to
"plat_is_smccc_feature_available" as per the current implementation.

Signed-off-by: Manish V Badarkhe <Manish.Badarkhe@arm.com>
Change-Id: Ib0fa400816fba61039c2029a9e127501a6a36811
1 file changed