xhci: Fix memory leak when caching protocol extended capability PSI tables - take 2

xhci: Fix memory leak when caching protocol extended capability PSI tables - take 2

xhci driver assumed that xHC controllers have at most one custom
supported speed table (PSI) for all usb 3.x ports.
Memory was allocated for one PSI table under the xhci hub structure.

Turns out this is not the case, some controllers have a separate
"supported protocol capability" entry with a PSI table for each port.
This means each usb3 roothub port can in theory support different custom
speeds.

To solve this, cache all supported protocol capabilities with their PSI
tables in an array, and add pointers to the xhci port structure so that
every port points to its capability entry in the array.

When creating the SuperSpeedPlus USB Device Capability BOS descriptor
for the xhci USB 3.1 roothub we for now will use only data from the
first USB 3.1 capable protocol capability entry in the array.
This could be improved later, this patch focuses resolving
the memory leak.

Reported-by: Paul Menzel <pmenzel@molgen.mpg.de>
Reported-by: Sajja Venkateswara Rao <VenkateswaraRao.Sajja@amd.com>
Fixes: 47189098f8be ("xhci: parse xhci protocol speed ID list for usb 3.1 usage")
Cc: stable <stable@vger.kernel.org> # v4.4+
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Link: https://lore.kernel.org/r/20200211150158.14475-1-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>