common: Drop init.h from common header

Move this uncommon header out of the common header.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/arm/mach-tegra/tegra20/clock.c b/arch/arm/mach-tegra/tegra20/clock.c
index 8f1bb4f..4e60781 100644
--- a/arch/arm/mach-tegra/tegra20/clock.c
+++ b/arch/arm/mach-tegra/tegra20/clock.c
@@ -9,6 +9,7 @@
 
 #include <common.h>
 #include <errno.h>
+#include <init.h>
 #include <asm/io.h>
 #include <asm/arch/clock.h>
 #include <asm/arch/tegra.h>