rockchip: jerry: Add support for timing SPI flash speed

Add the 'time' and 'sf test' commands so that we can test SPI flash
performance.

Signed-off-by: Simon Glass <sjg@chromium.org>

include/configs/chromebook_jerry.h

@@ -20,6 +20,9 @@
 #define CONFIG_SPL_SPI_LOAD
 #define CONFIG_SPI_FLASH_GIGADEVICE
 
+#define CONFIG_CMD_SF_TEST
+#define CONFIG_CMD_TIME
+
 #undef CONFIG_SPL_GPIO_SUPPORT
 
 #define CONFIG_KEYBOARD