[PATCH] usb: make module xhci_hcd removable

[Arthur Demchenkov <spinal.by@gmail.com>]

Fixed regression. After commit 29e409f the module xhci_hcd became
non-removable. That behaviour is not expected and there're no notes
about it in commit message. The module should be removable as it
blocks PM suspend/resume functions (Debian Bug#666406).

Signed-off-by: Arthur Demchenkov <spinal.by@gmail.com>
---
 drivers/usb/host/xhci.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index ec8ac16..4299cbf 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -5011,4 +5011,12 @@ static int __init xhci_hcd_init(void)
 	BUILD_BUG_ON(sizeof(struct xhci_run_regs) != (8+8*128)*32/8);
 	return 0;
 }
+
+/*
+ * If an init function is provided, an exit function must also be provided
+ * to allow module unload.
+ */
+static void __exit xhci_hcd_fini(void) { }
+
 module_init(xhci_hcd_init);
+module_exit(xhci_hcd_fini);
-- 
2.3.6