Add Ingenic X1000 serial support

Subject: Add Ingenic X1000 serial support
From: Zhou Yanjie <zhouyanjie@xxxxxxxx>
Date: Tue, 29 Jan 2019 01:03:47 +0800
Cc: linux-kernel@xxxxxxxxxxxxxxx, linux-serial@xxxxxxxxxxxxxxx, devicetree@xxxxxxxxxxxxxxx, robh+dt@xxxxxxxxxx, paul.burton@xxxxxxxx, gregkh@xxxxxxxxxxxxxxxxxxx, jslaby@xxxxxxxx, mark.rutland@xxxxxxx, syq@xxxxxxxxxx, jiaxun.yang@xxxxxxxxxxx, 772753199@xxxxxx
In-reply-to: <1548667176-119830-1-git-send-email-zhouyanjie@zoho.com>

v1->v2: Remove unnecessary "EARLYCON_DECLARE".
v2->v3: Use different subject line for each patch.

Follow-Ups:
- [PATCH v3 2/2] Dt-bindings: Serial: Add X1000 serial bindings.
  - From: Zhou Yanjie
- [PATCH v3 1/2] Serial: Ingenic: Add support for the X1000.
  - From: Zhou Yanjie