usb: ehci-omap: Drop surplus include

The EHCI OMAP driver includes <linux/gpio.h> but does not use
any symbols from this file, so drop it.

Cc: Roger Quadros <rogerq@ti.com>
Cc: Tony Lindgren <tony@atomide.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Link: https://lore.kernel.org/r/20200703131059.515436-1-linus.walleij@linaro.orgSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/host/ehci-omap.c

@@ -24,7 +24,6 @@
 #include <linux/slab.h>
 #include <linux/usb/ulpi.h>
 #include <linux/pm_runtime.h>
-#include <linux/gpio.h>
 #include <linux/clk.h>
 #include <linux/usb.h>
 #include <linux/usb/hcd.h>