nvidia/tegra*: check bus number for i2c driver APIs

BRANCH=None
BUG=None
TEST=emerge-foster coreboot

Change-Id: I383d2b5f269ed348065a9f270f80514a2ff45742
Signed-off-by: Patrick Georgi <pgeorgi@chromium.org>
Original-Commit-Id: fba6973c304e1612a9869c2e78a08650b6e5fe66
Original-Change-Id: I6d5d0098db8dbfb21529bf112a04b97779a0f381
Original-Signed-off-by: Yen Lin <yelin@nvidia.com>
Original-Reviewed-on: https://chromium-review.googlesource.com/264027
Original-Reviewed-by: Furquan Shaikh <furquan@chromium.org>
Reviewed-on: http://review.coreboot.org/9913
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>

src/soc/nvidia/tegra124/i2c.c

@@ -53,3 +53,5 @@ struct tegra_i2c_bus_info tegra_i2c_info[] = {
 		.reset_func = &clock_reset_x
 	}
 };
+
+unsigned g_num_i2c_buses = ARRAY_SIZE(tegra_i2c_info);