xilinx_spi: Split into of driver and generic part.

This patch splits the xilinx_spi driver into a generic part and a
OF driver part.

The reason for this is to later add in a platform driver as well.

Tested-by: John Linn <John.Linn@xilinx.com>
Signed-off-by: Richard Röjfors <richard.rojfors@mocean-labs.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
index e3f092a..01c4095 100644
--- a/drivers/spi/Makefile
+++ b/drivers/spi/Makefile
@@ -32,6 +32,7 @@
 obj-$(CONFIG_SPI_S3C24XX)		+= spi_s3c24xx.o
 obj-$(CONFIG_SPI_TXX9)			+= spi_txx9.o
 obj-$(CONFIG_SPI_XILINX)		+= xilinx_spi.o
+obj-$(CONFIG_SPI_XILINX_OF)		+= xilinx_spi_of.o
 obj-$(CONFIG_SPI_SH_SCI)		+= spi_sh_sci.o
 obj-$(CONFIG_SPI_STMP3XXX)		+= spi_stmp.o
 # 	... add above this line ...