qcacld-3.0: iwpriv return US regardless of any countrycode

Currently iw_get_channel_list_with_cc is not providing correct
channel list info.
To address this issue need to replace the legacy function
sme_get_country_code and update iw_get_channel_list function.

Change-Id: I28e059d8bde48392edd745463f7d667be233c473
CRs-Fixed: 3236375