USB: remove optional bus bindings in isp1760, fixing runtime warning

Roland Reported the following:
| kmem_cache_create: duplicate cache isp1760_qtd
| Pid: 461, comm: modprobe Tainted: G        W  2.6.28-rc2-git3-default #4
| Call Trace:
|  [<c017540e>] kmem_cache_create+0xc9/0x3a3
|  [<c0159a8d>] free_pages_bulk+0x16c/0x1c9
|  [<f165c05f>] isp1760_init+0x0/0xb [isp1760]
|  [<f165c018>] init_kmem_once+0x18/0x5f [isp1760]
|  [<f165c064>] isp1760_init+0x5/0xb [isp1760]
|  [<c010113d>] _stext+0x4d/0x148
|  [<c0142936>] load_module+0x12cd/0x142e
|  [<c01743c4>] kmem_cache_destroy+0x0/0xd7
|  [<c0142b1e>] sys_init_module+0x87/0x176
|  [<c01039eb>] sysenter_do_call+0x12/0x2f

The reason, is that ret is initialized with ENODEV instead of 0 _or_
the kmem cache is not freed in error case with no bus binding.

The difference between OF+PCI and OF only is
| 15148     804      32   15984    3e70 isp1760-of-pci.o
| 13748     676       8   14432    3860 isp1760-of.o

about 1.5 KiB.

Until there is a checkbox where the user *must* select atleast one item,
and may select multiple entries I don't make it selectable anymore.
Having a driver which can't be used under any circumstances is broken
anyway and I've seen distros shipping it that way.
Reported-by: Roland Kletzing <devzero@web.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>a
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/usb/host/Kconfig

@@ -110,29 +110,18 @@ config USB_ISP116X_HCD
 
 config USB_ISP1760_HCD
 	tristate "ISP 1760 HCD support"
-	depends on USB && EXPERIMENTAL
+	depends on USB && EXPERIMENTAL && (PCI || PPC_OF)
 	---help---
 	  The ISP1760 chip is a USB 2.0 host controller.
 
 	  This driver does not support isochronous transfers or OTG.
+	  This USB controller is usually attached to a non-DMA-Master
+	  capable bus. NXP's eval kit brings this chip on PCI card
+	  where the chip itself is behind a PLB to simulate such
+	  a bus.
 
 	  To compile this driver as a module, choose M here: the
-	  module will be called isp1760-hcd.
-
-config USB_ISP1760_PCI
-	bool "Support for the PCI bus"
-	depends on USB_ISP1760_HCD && PCI
-	---help---
-	  Enables support for the device present on the PCI bus.
-	  This should only be required if you happen to have the eval kit from
-	  NXP and you are going to test it.
-
-config USB_ISP1760_OF
-	bool "Support for the OF platform bus"
-	depends on USB_ISP1760_HCD && PPC_OF
-	---help---
-	  Enables support for the device present on the PowerPC
-	  OpenFirmware platform bus.
+	  module will be called isp1760.
 
 config USB_OHCI_HCD
 	tristate "OHCI HCD support"

drivers/usb/host/isp1760-if.c

@@ -14,16 +14,16 @@
 #include "../core/hcd.h"
 #include "isp1760-hcd.h"
 
-#ifdef CONFIG_USB_ISP1760_OF
+#ifdef CONFIG_PPC_OF
 #include <linux/of.h>
 #include <linux/of_platform.h>
 #endif
 
-#ifdef CONFIG_USB_ISP1760_PCI
+#ifdef CONFIG_PCI
 #include <linux/pci.h>
 #endif
 
-#ifdef CONFIG_USB_ISP1760_OF
+#ifdef CONFIG_PPC_OF
 static int of_isp1760_probe(struct of_device *dev,
 		const struct of_device_id *match)
 {
@@ -128,7 +128,7 @@ static struct of_platform_driver isp1760_of_driver = {
 };
 #endif
 
-#ifdef CONFIG_USB_ISP1760_PCI
+#ifdef CONFIG_PCI
 static u32 nxp_pci_io_base;
 static u32 iolength;
 static u32 pci_mem_phy0;
@@ -288,28 +288,28 @@ static struct pci_driver isp1761_pci_driver = {
 
 static int __init isp1760_init(void)
 {
-	int ret = -ENODEV;
+	int ret;
 
 	init_kmem_once();
 
-#ifdef CONFIG_USB_ISP1760_OF
+#ifdef CONFIG_PPC_OF
 	ret = of_register_platform_driver(&isp1760_of_driver);
 	if (ret) {
 		deinit_kmem_cache();
 		return ret;
 	}
 #endif
-#ifdef CONFIG_USB_ISP1760_PCI
+#ifdef CONFIG_PCI
 	ret = pci_register_driver(&isp1761_pci_driver);
 	if (ret)
 		goto unreg_of;
 #endif
 	return ret;
 
-#ifdef CONFIG_USB_ISP1760_PCI
+#ifdef CONFIG_PCI
 unreg_of:
 #endif
-#ifdef CONFIG_USB_ISP1760_OF
+#ifdef CONFIG_PPC_OF
 	of_unregister_platform_driver(&isp1760_of_driver);
 #endif
 	deinit_kmem_cache();
@@ -319,10 +319,10 @@ module_init(isp1760_init);
 
 static void __exit isp1760_exit(void)
 {
-#ifdef CONFIG_USB_ISP1760_OF
+#ifdef CONFIG_PPC_OF
 	of_unregister_platform_driver(&isp1760_of_driver);
 #endif
-#ifdef CONFIG_USB_ISP1760_PCI
+#ifdef CONFIG_PCI
 	pci_unregister_driver(&isp1761_pci_driver);
 #endif
 	deinit_kmem_cache();