uboot-imx

dm: spi: Rename soft_spi.c to soft_spi_legacy.c

Reserve the 'normal' name for use by driver model, and rename the old
driver so that it is clear that it is for 'legacy' drivers only.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Jagannadha Sutradharudu Teki <jagannadh.teki@gmail.com>