spi/mpc8xxx: refactor the common code for SPI/eSPI controller

Refactor the common code in file spi_fsl_spi.c to spi_fsl_lib.c used
by SPI/eSPI controller driver as a library, and leave the QE/CPM SPI
controller code in the SPI controller driver spi_fsl_spi.c.

Because the register map of the SPI controller and eSPI controller
is so different, also leave the code operated the register to the
driver code, not the common code.

Signed-off-by: Mingkai Hu <Mingkai.hu@freescale.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index e8f02a6..0e66194 100644
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -182,9 +182,14 @@
 	  This enables using the Freescale MPC5121 Programmable Serial
 	  Controller in SPI master mode.
 
+config SPI_FSL_LIB
+	tristate
+	depends on FSL_SOC
+
 config SPI_FSL_SPI
 	tristate "Freescale SPI controller"
 	depends on FSL_SOC
+	select SPI_FSL_LIB
 	help
 	  This enables using the Freescale SPI controllers in master mode.
 	  MPC83xx platform uses the controller in cpu mode or CPM/QE mode.