usb: core: hub: do error out if usb_autopm_get_interface() fails

Reviewing a fresh portion of coverity defects in USB core
(specifically CID 1458999), Alan Stern noted below in [1]:

On Tue, Feb 25, 2020 at 02:39:23PM -0500, Alan Stern wrote:
 > A revised search finds line 997 in drivers/usb/core/hub.c and lines
 > 216, 269 in drivers/usb/core/port.c.  (I didn't try looking in any
 > other directories.)  AFAICT all three of these should check the
 > return value, although a error message in the kernel log probably
 > isn't needed.

Factor out the usb_remove_device() change into a standalone patch to
allow conflict-free integration on top of the earliest stable branches.

[1] https://lore.kernel.org/lkml/[email protected]

Fixes: 253e057 ("USB: add a "remove hardware" sysfs attribute")
Cc: [email protected] # v2.6.33+
Suggested-by: Alan Stern <[email protected]>
Signed-off-by: Eugeniu Rosca <[email protected]>
Acked-by: Alan Stern <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

drivers/usb/core/hub.c

@@ -988,13 +988,17 @@ int usb_remove_device(struct usb_device *udev)
 {
 	struct usb_hub *hub;
 	struct usb_interface *intf;
+	int ret;
 
 	if (!udev->parent)	/* Can't remove a root hub */
 		return -EINVAL;
 	hub = usb_hub_to_struct_hub(udev->parent);
 	intf = to_usb_interface(hub->intfdev);
 
-	usb_autopm_get_interface(intf);
+	ret = usb_autopm_get_interface(intf);
+	if (ret < 0)
+		return ret;
+
 	set_bit(udev->portnum, hub->removed_bits);
 	hub_port_logical_disconnect(hub, udev->portnum);
 	usb_autopm_put_interface(intf);