SPI: Add support for TSC2101

The new driver is functionally the same as the old
drivers/ssi/omap-tsc2101 driver in the linux-omap tree.

Signed-off-by: Imre Deak <imre.deak@solidboot.com>

diff --cc drivers/spi/Kconfig
Simple merge

diff --cc drivers/spi/Makefile
Simple merge

diff --cc drivers/spi/tsc2101.c
Simple merge

diff --cc include/linux/spi/tsc2101.h
Simple merge