xhci: check port array allocation was successful before dereferencing it

xhci: check port array allocation was successful before dereferencing it

BugLink: https://bugs.launchpad.net/bugs/1928857
[ Upstream commit 8a157d2ff104d2849c58226a1fd02365d7d60150 ]

return if rhub->ports is null after rhub->ports = kcalloc_node()
Klockwork reported issue

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20210406070208.3406266-2-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>