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/riscv/cpu/cpu.c b/arch/riscv/cpu/cpu.c
index e457f6a..1cebb03 100644
--- a/arch/riscv/cpu/cpu.c
+++ b/arch/riscv/cpu/cpu.c
@@ -6,6 +6,7 @@
 #include <common.h>
 #include <cpu.h>
 #include <dm.h>
+#include <init.h>
 #include <log.h>
 #include <asm/encoding.h>
 #include <dm/uclass-internal.h>