wifi: mac80211_hwsim: add 6 GHz EHT Mesh capabilities

To facilitate testing of mesh EHT 320 MHz, add support for advertising
this capability.

Signed-off-by: Aditya Kumar Singh <quic_adisi@quicinc.com>
Link: https://patch.msgid.link/20241119-mesh_320mhz_support-v1-2-f9463338d584@quicinc.com


Signed-off-by: Johannes Berg <johannes.berg@intel.com>