In the xHCI driver, configure endpoint commands that are submitted to the
hardware may involve one of two data structures.  If the configure
endpoint command is setting up a new configuration or modifying max packet
sizes, the data structures and completions are statically allocated in the
xhci_virt_device structure.  If the command is being used to set up
streams or add hub information, then the data structures are dynamically
allocated, and placed on a device command waiting list.

Break out the code to check whether a completed command is in the device
command waiting list.  Fix a subtle bug in the old code: continue
processing the command if the command isn't in the wait list.  In the old
code, if there was a command in the wait list, but it didn't match the
completed command, the completed command event would be dropped.
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>