80211_resource cannot detect AC capability in Trusty

i'll give this to Sylvain who worked on the resource initially; I tried debugging this but couldn't, and iw list on my laptop doesn't report AC support, even though my chipset is in theory the same:

02:00.0 Network controller [0280]: Intel Corporation Wireless 7260 [8086:08b1] (rev 6b)
        Subsystem: Intel Corporation Dual Band Wireless-AC 7260 [8086:c470]
        Flags: bus master, fast devsel, latency 0, IRQ 60
        Memory at f0400000 (64-bit, non-prefetchable) [size=8K]
        Capabilities: [c8] Power Management version 3
        Capabilities: [d0] MSI: Enable+ Count=1/1 Maskable- 64bit+
        Capabilities: [40] Express Endpoint, MSI 00
        Capabilities: [100] Advanced Error Reporting
        Capabilities: [140] Device Serial Number 7c-7a-91-ff-ff-27-1f-5a
        Capabilities: [14c] Latency Tolerance Reporting
        Capabilities: [154] Vendor Specific Information: ID=cafe Rev=1 Len=014 <?>
        Kernel driver in use: iwlwifi

I don't know if it's because I have no AC-capable routers.

Result of my tests, it's a typo in configure.ac where we have to llok for NL80211_BAND_ATTR_VHT_MCS_SET not NL80211_BAND_ATTR_VHT_MSC_SET (note the "MSC" instead of "MCS").