media: go7007: fix memory leak in go7007_usb_probe

In commit 137641287e ("go7007: add sanity checking for endpoints")
endpoint sanity check was introduced, but if check fails it simply
returns with leaked pointers.

Cutted log from my local syzbot instance:

BUG: memory leak
unreferenced object 0xffff8880209f0000 (size 8192):
  comm "kworker/0:4", pid 4916, jiffies 4295263583 (age 29.310s)
  hex dump (first 32 bytes):
    30 b0 27 22 80 88 ff ff 75 73 62 2d 64 75 6d 6d  0.'"....usb-dumm
    79 5f 68 63 64 2e 33 2d 31 00 00 00 00 00 00 00  y_hcd.3-1.......
  backtrace:
    [<ffffffff860ca856>] kmalloc include/linux/slab.h:556 [inline]
    [<ffffffff860ca856>] kzalloc include/linux/slab.h:686 [inline]
    [<ffffffff860ca856>] go7007_alloc+0x46/0xb40 drivers/media/usb/go7007/go7007-driver.c:696
    [<ffffffff860de74e>] go7007_usb_probe+0x13e/0x2200 drivers/media/usb/go7007/go7007-usb.c:1114
    [<ffffffff854a5f74>] usb_probe_interface+0x314/0x7f0 drivers/usb/core/driver.c:396
    [<ffffffff845a7151>] really_probe+0x291/0xf60 drivers/base/dd.c:576

BUG: memory leak
unreferenced object 0xffff88801e2f2800 (size 512):
  comm "kworker/0:4", pid 4916, jiffies 4295263583 (age 29.310s)
  hex dump (first 32 bytes):
    00 87 40 8a ff ff ff ff 00 00 00 00 00 00 00 00  ..@.............
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<ffffffff860de794>] kmalloc include/linux/slab.h:556 [inline]
    [<ffffffff860de794>] kzalloc include/linux/slab.h:686 [inline]
    [<ffffffff860de794>] go7007_usb_probe+0x184/0x2200 drivers/media/usb/go7007/go7007-usb.c:1118
    [<ffffffff854a5f74>] usb_probe_interface+0x314/0x7f0 drivers/usb/core/driver.c:396
    [<ffffffff845a7151>] really_probe+0x291/0xf60 drivers/base/dd.c:576

Fixes: 137641287e ("go7007: add sanity checking for endpoints")
Signed-off-by: Pavel Skripkin <paskripkin@gmail.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

drivers/media/usb/go7007/go7007-usb.c

@@ -1134,7 +1134,7 @@ static int go7007_usb_probe(struct usb_interface *intf,
 
 	ep = usb->usbdev->ep_in[4];
 	if (!ep)
-		return -ENODEV;
+		goto allocfail;
 
 	/* Allocate the URB and buffer for receiving incoming interrupts */
 	usb->intr_urb = usb_alloc_urb(0, GFP_KERNEL);