rockchip: rk3399: split roc-pc-rk3399 out of evb_rk3399

roc-pc-rk3399 board has one user button & three user LED's. Currently
we don't have any code support for these devices. Since button and LED's are
specific to roc-pc-rk3399 board, split it into its own board file and add code
support here.

Signed-off-by: Suniel Mahesh <sunil@amarulasolutions.com>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>
diff --git a/board/firefly/roc-pc-rk3399/MAINTAINERS b/board/firefly/roc-pc-rk3399/MAINTAINERS
new file mode 100644
index 0000000..7564dd2
--- /dev/null
+++ b/board/firefly/roc-pc-rk3399/MAINTAINERS
@@ -0,0 +1,6 @@
+ROC-RK3399-PC
+M:	Levin Du <djw@t-chip.com.cn>
+S:	Maintained
+F:	board/firefly/roc-pc-rk3399
+F:	include/configs/roc-pc-rk3399.h
+F:	configs/roc-pc-rk3399_defconfig