clk: tegra: Fix periph_clk_to_bit macro

The parameter name should be "gate", not "periph".  This worked, however,
because it happens that everywhere periph_clk_to_bit is called, "gate" was
in the local scope.

Signed-off-by: Yen Lin <yelin@nvidia.com>
Signed-off-by: Andrew Chew <achew@nvidia.com>
Reviewed-by: Thierry Reding <thierry.reding@avionic-design.de>
Reviewed-by: Prashant Gaikwad <pgaikwad@nvidia.com>
Acked-by: Peter De Schrijver <pdeschrijver@nvidia.com>
Acked-by: Mike Turquette <mturquette@linaro.org>
Signed-off-by: Stephen Warren <swarren@nvidia.com>