ARM: tegra: call tegra_board_init on Tegra186

Introduce tegra_board_init() and call it from board_init(). Tegra wil use
tegra_board_init() for board-specific initialization, and board_init() for
SoC-specific initialization.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Tom Warren <twarren@nvidia.com>

arch/arm/mach-tegra/board186.c

@@ -16,11 +16,16 @@ int board_early_init_f(void)
 	return 0;
 }
 
-int board_init(void)
+__weak int tegra_board_init(void)
 {
 	return 0;
 }
 
+int board_init(void)
+{
+	return tegra_board_init();
+}
+
 int board_late_init(void)
 {
 	return 0;