spi: npcm-fiu: add NPCM7xx FIU controller driver

Add Nuvoton NPCM BMC Flash Interface Unit(FIU) SPI master
controller driver using SPI-MEM interface.

The FIU supports single, dual or quad communication interface.
The FIU controller driver provides flash access in UMA(User
Mode Access) mode by using an indirect address/data mechanism.

the dts node is followed upstream kernel dts name.

Signed-off-by: Jim Liu <JJLIU0@nuvoton.com>
Signed-off-by: Stanley Chu <yschu@nuvoton.com>
Reviewed-by: Jagan Teki <jagan@amarulasolutions.com>
[Jagan: fixed the Kconfig, Makefile order]
Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
index 7f43f84..06e81b4 100644
--- a/drivers/spi/Makefile
+++ b/drivers/spi/Makefile
@@ -47,6 +47,7 @@
 obj-$(CONFIG_MVEBU_A3700_SPI) += mvebu_a3700_spi.o
 obj-$(CONFIG_MXC_SPI) += mxc_spi.o
 obj-$(CONFIG_MXS_SPI) += mxs_spi.o
+obj-$(CONFIG_NPCM_FIU_SPI) += npcm_fiu_spi.o
 obj-$(CONFIG_NXP_FSPI) += nxp_fspi.o
 obj-$(CONFIG_ATCSPI200_SPI) += atcspi200_spi.o
 obj-$(CONFIG_OCTEON_SPI) += octeon_spi.o