xhci: Reconfigure endpoint 0 max packet size only during endpoint reset

The max packet size for full speed control endpoint 0 may vary. It is
defined in the device descriptor, which is read using the same endpoint.
Usb core sets a temporary max packet size value until the real value is
read.

xhci driver needs to reconfigure the endpoint context seen by the
controller if the max packet size changes.
It makes more sense to do this reconfiguration in xhci_endpoint_reset()
instead of urb enqueue as usb core will call endpoint reset during
enumeration if the max packet values differ.
Max packet size adjustment for endpoint 0 can only happen once per
device enumeration.

Previously the max packet size was checked during every urb enqueue.
This is an additional check for every enqueued urb, and also turned out
to have locking issues as urbs may be queued in any context while xhci
max packet size reconfiguration requires memory allocation, locking, and
sleeping.

Tested with a full speed device using both old and new scheme enumeration
and an intentionally incorrect preliminary max packet size value.

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20231201150647.1307406-19-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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