usb_mass_storage: make cable check conditional on CONFIG_USB_CABLE_CHECK

Signed-off-by: Eric Nelson <eric.nelson@boundarydevices.com>
nitrogen6x: default to PCI disabled

Signed-off-by: Eric Nelson <eric.nelson@boundarydevices.com>
nitrogen6x: hack at USB Mass Storage support (not functional)

Signed-off-by: Eric Nelson <eric.nelson@boundarydevices.com>
nitrogen6x: compile USB Mass Storage (not yet functional)

Signed-off-by: Eric Nelson <eric.nelson@boundarydevices.com>