As QCA6390 does not support mesh interfaces, move the interface_modes to
hw_params. Also create interface combinations dynamically so that it's easy to
change the values.

Now QCA6390 does not claim to support mesh interfaces to user space, but
IPQ8074 continues to do that.

Tested-on: QCA6390 hw2.0 PCI WLAN.HST.1.0.1-01740-QCAHSTSWPLZ_V2_TO_X86-1
Signed-off-by: NKalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/1601399736-3210-4-git-send-email-kvalo@codeaurora.org