spi: Add Amlogic Meson SPI Flash Controller driver

The Amlogic Meson SoCs embeds a Flash oriented SPI Controller name SPIFC.
This driver, ported from the Linux meson-spi-spifc driver, add support
for this controller on the Amlogic Meson GX SoCs in U-Boot.

Tested-by: Jerome Brunet <jbrunet@baylibre.com>
Reviewed-by: Jagan Teki <jagan@openedev.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index 516188e..6085788 100644
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -116,6 +116,14 @@
 	  access the SPI NOR flash on platforms embedding this Intel
 	  ICH IP core.
 
+config MESON_SPIFC
+	bool "Amlogic Meson SPI Flash Controller driver"
+	depends on ARCH_MESON
+	help
+	  Enable the Amlogic Meson SPI Flash Controller SPIFC) driver.
+	  This driver can be used to access the SPI NOR flash chips on
+	  Amlogic Meson SoCs.
+
 config MT7621_SPI
 	bool "MediaTek MT7621 SPI driver"
 	depends on ARCH_MT7620