usb: xhci: Remove in_interrupt() checks

usb: xhci: Remove in_interrupt() checks

The usage of in_interrupt() in drivers is phased out for various reasons.

xhci_set_hc_event_deq() has an !in_interrupt() check which is pointless
because the function is only invoked from xhci_mem_init() which is clearly
task context as it does GFP_KERNEL allocations. Remove it.

xhci_urb_enqueue() prints a debug message if an URB is submitted after the
underlying hardware was suspended. But that warning is only issued when
in_interrupt() is true, which makes no sense. Simply return -ESHUTDOWN and
be done with it.

Signed-off-by: Ahmed S. Darwish <a.darwish@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Mathias Nyman <mathias.nyman@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-usb@vger.kernel.org
Link: https://lore.kernel.org/r/20201019101110.148631116@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>