board: zyxel: Remove <common.h> and add needed includes

Remove <common.h> from this board vendor directory and when needed
add missing include files directly.

Signed-off-by: Tom Rini <trini@konsulko.com>
---
Cc: Tony Dinh <mibodhi@gmail.com>
Cc: Luka Perkov <luka.perkov@sartura.hr>
diff --git a/board/zyxel/nsa310s/nsa310s.c b/board/zyxel/nsa310s/nsa310s.c
index b3ea660..d018b57 100644
--- a/board/zyxel/nsa310s/nsa310s.c
+++ b/board/zyxel/nsa310s/nsa310s.c
@@ -4,7 +4,6 @@
  * Copyright (C) 2015 Gerald Kerma <dreagle@doukki.net>
  */
 
-#include <common.h>
 #include <init.h>
 #include <netdev.h>
 #include <asm/arch/cpu.h>
diff --git a/board/zyxel/nsa325/nsa325.c b/board/zyxel/nsa325/nsa325.c
index f5f63ee..38340b3 100644
--- a/board/zyxel/nsa325/nsa325.c
+++ b/board/zyxel/nsa325/nsa325.c
@@ -14,7 +14,6 @@
  * Marvell Semiconductor <www.marvell.com>
  */
 
-#include <common.h>
 #include <asm/arch/soc.h>
 #include <asm/arch/mpp.h>
 #include <netdev.h>