rockchip: px30: support px30

px30 is a Quad-core soc and Cortex-a53 inside.
This patch supports the following functions:
1. basic platform setup
2. power up/off cpus
3. suspend/resume cpus
4. suspend/resume system
5. reset system
6. power off system

Change-Id: I73d55aa978096c078242be921abe0ddca9e8f67e
Signed-off-by: XiaoDong Huang <derrick.huang@rock-chips.com>
diff --git a/docs/plat/rockchip.rst b/docs/plat/rockchip.rst
index cee35e4..b7c43fb 100644
--- a/docs/plat/rockchip.rst
+++ b/docs/plat/rockchip.rst
@@ -5,6 +5,7 @@
 AARCH32 and AARCH64 fields.
 
 This includes right now:
+-  px30: Quad-Core Cortex-A53
 -  rk3288: Quad-Core Cortex-A17 (past A12)
 -  rk3328: Quad-Core Cortex-A53
 -  rk3368: Octa-Core Cortex-A53