Revert "Import WifiChannelWidthInMhz from the Vendor HAL interface"

This reverts commit fcf51b499d4d6848856671322ec467860b9d9a91.

Reason for revert: Causing large increase in supplicant memory usage. See b/319972675

Change-Id: I784603d449aa8e6592405ac5803bc9cd58bc5bd7
5 files changed