spi: omap-100k: Drop include

The OMAP-100k driver includes <linux/gpio.h> but does not
use any symbols from it, so drop the include.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20200714073357.34879-1-linus.walleij@linaro.orgSigned-off-by: Mark Brown <broonie@kernel.org>

drivers/spi/spi-omap-100k.c

@@ -19,7 +19,6 @@
 #include <linux/err.h>
 #include <linux/clk.h>
 #include <linux/io.h>
-#include <linux/gpio.h>
 #include <linux/slab.h>
 
 #include <linux/spi/spi.h>