mips: bmips: enable the SPI flash on the Netgear CG3100D

It's a Spansion (s25fl064a) 8 MB SPI flash.

Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
Reviewed-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Reviewed-by: Jagan Teki <jagan@openedev.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

arch/mips/dts/netgear,cg3100d.dts

@@ -90,6 +90,18 @@
 	status = "okay";
 };
 
+&spi {
+	status = "okay";
+
+	spi-flash@0 {
+		compatible = "spi-flash";
+		reg = <0>;
+		#address-cells = <1>;
+		#size-cells = <1>;
+		spi-max-frequency = <25000000>;
+	};
+};
+
 &uart0 {
 	u-boot,dm-pre-reloc;
 	status = "okay";

configs/netgear_cg3100d_ram_defconfig

@@ -25,6 +25,8 @@ CONFIG_CMD_MEMINFO=y
 # CONFIG_CMD_FLASH is not set
 # CONFIG_CMD_FPGA is not set
 # CONFIG_CMD_LOADS is not set
+CONFIG_CMD_SF=y
+CONFIG_CMD_SPI=y
 # CONFIG_CMD_NET is not set
 # CONFIG_CMD_NFS is not set
 # CONFIG_CMD_MISC is not set
@@ -35,9 +37,15 @@ CONFIG_LED=y
 CONFIG_LED_BCM6328=y
 CONFIG_LED_BLINK=y
 CONFIG_LED_GPIO=y
+CONFIG_DM_SPI_FLASH=y
+CONFIG_SPI_FLASH=y
+CONFIG_SPI_FLASH_SPANSION=y
+CONFIG_SPI_FLASH_MTD=y
 CONFIG_DM_RESET=y
 CONFIG_RESET_BCM6345=y
 # CONFIG_SPL_SERIAL_PRESENT is not set
 CONFIG_DM_SERIAL=y
 CONFIG_BCM6345_SERIAL=y
+CONFIG_DM_SPI=y
+CONFIG_BCM63XX_SPI=y
 CONFIG_WDT_BCM6345=y