usb: isp1301-omap: Fix the GPIO include

The file is using only GPIO descriptors, so only include
<linux/gpio/consumer.h> instead of the legacy include.

This is a non-urgent fix.

Fixes: f3ef3816

 ("usb: isp1301-omap: Convert to use GPIO descriptors")
Cc: Tony Lindgren <tony@atomide.com>
Cc: Felipe Balbi <balbi@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20210720200336.223398-1-linus.walleij@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>