Change the default country setting to US

By default turn off some 2.4GHz wifi channels per FCC regulation. It
can still be updated via MTK's wifitesttool.

The country code is set as 'U' 'S' in the little endien, consistent with
the function implementation of rlmDomainAlpha2ToU32.

Change-Id: I091571f676891e7226b1ad474e3a704fd123f161
1 file changed