xhci: don't kick in xhci_submit and xhci_fire_ctl_transfer

xhci_submit and xhci_fire_ctl_transfer are is called from
xhci_kick_epctx processing loop only, so there is no need to call
xhci_kick_epctx make sure processing continues.  Also eecursive calls
into xhci_kick_epctx can cause trouble.

Drop the xhci_kick_epctx calls.

Cc: 1653384@bugs.launchpad.net
Fixes: 94b037f2a451b3dc855f9f2c346e5049a361bd55
Reported-by: Fabian Lesniak <fabian@lesniak-it.de>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Message-id: 1485790607-31399-4-git-send-email-kraxel@redhat.com
