softap: Add BAND_60GHZ to SoftApConfiguration

Add band constant BAND_60GHZ to SoftApConfiguration,
needed for supporting SoftAP on the 60GHz band.

Bug: 147464239
Test: atest FrameworksWifiTests
Test: atest FrameworksWifiApiTests
Change-Id: I8903f2d0119392646cca8bb8d1d6c723ec61b4c3
9 files changed