spi: ep93xx: Repair SPI CS lookup tables

The actual device name of the SPI controller being registered on EP93xx is
"spi0" (as seen by gpiod_find_lookup_table()). This patch fixes all
relevant lookup tables and the following failure (seen on EDB9302):

ep93xx-spi ep93xx-spi.0: failed to register SPI master
ep93xx-spi: probe of ep93xx-spi.0 failed with error -22

Fixes: 1dfbf334 ("spi: ep93xx: Convert to use CS GPIO descriptors")
Cc: stable@vger.kernel.org
Signed-off-by: Alexander Sverdlin <alexander.sverdlin@gmail.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Lukasz Majewski <lukma@denx.de>
Link: https://lore.kernel.org/r/20190831180402.10008-1-alexander.sverdlin@gmail.com


Signed-off-by: Mark Brown <broonie@kernel.org>