roc-pc-rk3399: Enable SPI Flash

Enable winbond SPI flash for ROC-PC-RK3399 board.

Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>
diff --git a/configs/roc-pc-rk3399_defconfig b/configs/roc-pc-rk3399_defconfig
index 39c3e18..e51197c 100644
--- a/configs/roc-pc-rk3399_defconfig
+++ b/configs/roc-pc-rk3399_defconfig
@@ -42,6 +42,8 @@
 CONFIG_BAUDRATE=1500000
 CONFIG_DEBUG_UART_SHIFT=2
 CONFIG_SYSRESET=y
+CONFIG_SPI_FLASH_WINBOND=y
+CONFIG_ROCKCHIP_SPI=y
 CONFIG_USB=y
 CONFIG_USB_XHCI_HCD=y
 CONFIG_USB_XHCI_DWC3=y