ARM: OMAP: McSPI: Remove unused flag from struct omap2_mcspi_device_config

Flag single_channel in struct omap2_mcspi_device_config is not used
by drivers/spi/spi-omap2-mcspi.c so we may remove it from include/plat/mcspi.h
and affected board files.

Signed-off-by: Jarkko Nikula <jarkko.nikula@bitmer.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>

arch/arm/mach-omap2/common-board-devices.c

@@ -33,7 +33,6 @@
 	defined(CONFIG_TOUCHSCREEN_ADS7846_MODULE)
 static struct omap2_mcspi_device_config ads7846_mcspi_config = {
 	.turbo_mode	= 0,
-	.single_channel	= 1,	/* 0: slave, 1: master */
 };
 
 static struct ads7846_platform_data ads7846_config = {