uwb: avoid radio controller reset loops

If a radio controller reset attempt occurs while a probe() or remove()
is in progress it fails and is retried endlessly, potentially preventing
the probe() or remove() from completing.

If a reset fails, sleep for a bit before retrying the reset.  This
allows the probe()/remove() to complete.

Signed-off-by: David Vrabel <david.vrabel@csr.com>
diff --git a/drivers/uwb/hwa-rc.c b/drivers/uwb/hwa-rc.c
index 9052bcb..e7eeb63 100644
--- a/drivers/uwb/hwa-rc.c
+++ b/drivers/uwb/hwa-rc.c
@@ -887,8 +887,7 @@
 	struct hwarc *hwarc = usb_get_intfdata(iface);
 	struct uwb_rc *uwb_rc = hwarc->uwb_rc;
 
-	uwb_rc_post_reset(uwb_rc);
-	return 0;
+	return uwb_rc_post_reset(uwb_rc);
 }
 
 /** USB device ID's that we handle */