usb: gadget: use IS_ENABLED() instead of checking for built-in or module

The IS_ENABLED() macro checks if a Kconfig symbol has been enabled either
built-in or as a module, use that macro instead of open coding the same.

Using the macro makes the code more readable by helping abstract away some
of the Kconfig built-in and module enable details.

Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Acked-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/gadget/udc/omap_udc.c

@@ -2875,7 +2875,7 @@ bad_on_1710:
 	xceiv = NULL;
 	/* "udc" is now valid */
 	pullup_disable(udc);
-#if	defined(CONFIG_USB_OHCI_HCD) || defined(CONFIG_USB_OHCI_HCD_MODULE)
+#if	IS_ENABLED(CONFIG_USB_OHCI_HCD)
 	udc->gadget.is_otg = (config->otg != 0);
 #endif