ARM: OMAP1: fix omap_udc registration

omap_udc platform device is not registered properly anymore:
CONFIG_USB_GADGET_OMAP was deleted by 193ab2a6 (usb: gadget: allow
multiple gadgets to be built) already in v3.1.

Fix by using CONFIG_USB_OMAP instead. Tested on Nokia 770 by checking
that omap_udc is probed & working properly when built as a module.
Acked-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Signed-off-by: Tony Lindgren <tony@atomide.com>

arch/arm/mach-omap1/include/mach/usb.h

@@ -2,7 +2,7 @@
  * FIXME correct answer depends on hmc_mode,
  * as does (on omap1) any nonzero value for config->otg port number
  */
-#ifdef	CONFIG_USB_GADGET_OMAP
+#if IS_ENABLED(CONFIG_USB_OMAP)
 #define	is_usb0_device(config)	1
 #else
 #define	is_usb0_device(config)	0

arch/arm/mach-omap1/usb.c

@@ -123,7 +123,7 @@ omap_otg_init(struct omap_usb_config *config)
 	syscon = omap_readl(OTG_SYSCON_1);
 	syscon |= HST_IDLE_EN|DEV_IDLE_EN|OTG_IDLE_EN;
 
-#ifdef	CONFIG_USB_GADGET_OMAP
+#if IS_ENABLED(CONFIG_USB_OMAP)
 	if (config->otg || config->register_dev) {
 		struct platform_device *udc_device = config->udc_device;
 		int status;
@@ -169,7 +169,7 @@ omap_otg_init(struct omap_usb_config *config)
 void omap_otg_init(struct omap_usb_config *config) {}
 #endif
 
-#ifdef	CONFIG_USB_GADGET_OMAP
+#if IS_ENABLED(CONFIG_USB_OMAP)
 
 static struct resource udc_resources[] = {
 	/* order is significant! */
@@ -600,7 +600,7 @@ static void __init omap_1510_usb_init(struct omap_usb_config *config)
 	while (!(omap_readw(ULPD_DPLL_CTRL) & DPLL_LOCK))
 		cpu_relax();
 
-#ifdef	CONFIG_USB_GADGET_OMAP
+#if IS_ENABLED(CONFIG_USB_OMAP)
 	if (config->register_dev) {
 		int status;