staging: gasket: apex: fixup undefined PCI class

Apex chips with class 0 (PCI_CLASS_NOT_DEFINED) fixed up to
PCI_CLASS_SYSTEM_OTHER to enable PCI resource assignments.

Signed-off-by: Todd Poynor <toddpoynor@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>