rockchip: px30: Define variables for compressed image support

The standard boot path expects the kernel_comp_addr_r and kernel_comp_size
variables for booting compressed kernel images. Define them using the previous
kernel_addr_c value (likely initially meant for this purpose) and usual size.

This was tested on the PX30 EVB to successfully boot compressed Linux kernel
images.

Signed-off-by: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>
diff --git a/include/configs/px30_common.h b/include/configs/px30_common.h
index 6fbd267..13ed901 100644
--- a/include/configs/px30_common.h
+++ b/include/configs/px30_common.h
@@ -21,8 +21,9 @@
 	"pxefile_addr_r=0x00600000\0" \
 	"fdt_addr_r=0x08300000\0" \
 	"kernel_addr_r=0x00280000\0" \
-	"kernel_addr_c=0x03e80000\0" \
-	"ramdisk_addr_r=0x0a200000\0"
+	"ramdisk_addr_r=0x0a200000\0" \
+	"kernel_comp_addr_r=0x03e80000\0" \
+	"kernel_comp_size=0x2000000\0"
 
 #define CFG_EXTRA_ENV_SETTINGS \
 	ENV_MEM_LAYOUT_SETTINGS \