iwlwifi: support an additional Qu subsystem id

Add PCI subsystem ID 0x6074 for Qu family.

Signed-off-by: Golan Ben Ami <golan.ben.ami@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/iwlwifi.20201008180656.fba1c29fc217.I7d47c8de078d48cfc1c98ce1086e71d8d2ebb980@changeid