qcacld-3.0: Use frequency based channel enumerations

CONFIG_LEGACY_CHAN_ENUM has been removed. That macro needs channel number
based enumeration. Use channel frequency going forward. So change to
frequency based channel enumeration.

Change-Id: I234eb070a6dcfaf3325bbd523c19188d5b2bbd24
CRs-Fixed: 2513098
7 files changed