spi: Rename sun4i_spi.c into spi-sunxi.c

Now the same SPI controller driver is reusable in all Allwinner
SoC variants, so rename the existing sun4i_spi.c into spi-sunxi.c
which eventually look like a common sunxi driver.

Also update the function, variable, structure names in driver from
sun4i into sunxi.

Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>

drivers/spi/Kconfig

@@ -213,6 +213,13 @@ config SANDBOX_SPI
 		};
 	  };
 
+config SPI_SUNXI
+	bool "Allwinner SoC SPI controllers"
+	help
+	  Enable the Allwinner SoC SPi controller driver.
+
+	  Same controller driver can reuse in all Allwinner SoC variants.
+
 config STM32_QSPI
 	bool "STM32F7 QSPI driver"
 	depends on STM32F7
@@ -222,11 +229,6 @@ config STM32_QSPI
 	  used to access the SPI NOR flash chips on platforms embedding
 	  this ST IP core.
 
-config SUN4I_SPI
-	bool "Allwinner A10/A31 SoCs SPI controller"
-	help
-	  This enables using the SPI controller on the Allwinner A10/A31 SoCs.
-
 config TEGRA114_SPI
 	bool "nVidia Tegra114 SPI driver"
 	help

drivers/spi/Makefile

@@ -48,10 +48,10 @@ obj-$(CONFIG_PL022_SPI) += pl022_spi.o
 obj-$(CONFIG_RENESAS_RPC_SPI) += renesas_rpc_spi.o
 obj-$(CONFIG_ROCKCHIP_SPI) += rk_spi.o
 obj-$(CONFIG_SANDBOX_SPI) += sandbox_spi.o
+obj-$(CONFIG_SPI_SUNXI) += spi-sunxi.o
 obj-$(CONFIG_SH_SPI) += sh_spi.o
 obj-$(CONFIG_SH_QSPI) += sh_qspi.o
 obj-$(CONFIG_STM32_QSPI) += stm32_qspi.o
-obj-$(CONFIG_SUN4I_SPI) += sun4i_spi.o
 obj-$(CONFIG_TEGRA114_SPI) += tegra114_spi.o
 obj-$(CONFIG_TEGRA20_SFLASH) += tegra20_sflash.o
 obj-$(CONFIG_TEGRA20_SLINK) += tegra20_slink.o