usb: renesas_usbhs: Remove unneeded #include <linux/platform_data/gpio-rcar.h>

This header file will be removed soon.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Felipe Balbi <balbi@ti.com>