rockchip: doc: add GPT partition layout

A simple introduction.

Signed-off-by: Jacob Chen <jacob2.chen@rock-chips.com>
Acked-by: Simon Glass <sjg@chromium.org>

doc/README.rockchip

@@ -149,7 +149,6 @@ Note: rk3036 SDMMC and debug uart use the same iomux, so if you boot from SD, th
 
 Using fastboot on rk3288
 ========================
-- Define GPT partition layout like kylin_rk3036(see include/configs/kylin_rk3036.h)
 - Write GPT partition layout to mmc device which fastboot want to use it to
 store the image
 
@@ -212,7 +211,6 @@ When booting you should see something like:
    Err:   serial@ff690000
    =>
 
-
 Future work
 ===========
 
@@ -298,6 +296,15 @@ overhead and in SPL with a 32KB size limit some shortcuts have been taken.
 In general all Rockchip drivers should use these features, with SPL-specific
 modifications where required.
 
+GPT partition layout
+----------------------------
+
+Rockchip use a unified GPT partition layout  in open source support.
+With this GPT partition layout, uboot can be compatilbe with other components,
+like miniloader, trusted-os, arm-trust-firmware.
+
+There are some documents about partitions in the links below.
+http://rockchip.wikidot.com/partitions
 
 --
 Simon Glass <sjg@chromium.org>