Merge branch 'pci/workqueue'

- Add WQ_PERCPU to alloc_workqueue() users (Marco Crivellari)

- Replace use of system_wq with system_percpu_wq (Marco Crivellari)

- Check for failure of alloc_workqueue() to avoid NULL pointer dereferences
  (Haotian Zhang)

* pci/workqueue:
  PCI: endpoint: Add missing NULL check for alloc_workqueue()
  PCI: endpoint: Replace use of system_wq with system_percpu_wq
  PCI: Add WQ_PERCPU to alloc_workqueue() users

# Conflicts:
#	drivers/pci/endpoint/pci-ep-cfs.c