wlan:HT40 support on 2.4GHz band

Following changes are made as part of this gerrit
- Enabling HT40 on 2.4GHz
- Switching of HT40 to HT20
- Added new feature flag HT40_OBSS_SCAN
- Beacon offload extended to detect the changes in secondary
  channel offset in HT operation IE.

Change-Id: I0fdafde198f44c0d51a85e9beaade2b60c6ac174
CRs-Fixed: 608188
16 files changed
tree: 8fed4c85f6378006253fa05d35e633ea740f1bae
  1. CORE/
  2. firmware_bin/
  3. riva/
  4. Android.mk
  5. Kbuild
  6. Kconfig