Revert "net: wireless: update db.txt for WLAN"

This reverts commit d8a1c5fd.
The db.txt files depends on a feature that was removed by
commit c8c240e2 ("cfg80211: reg: remove support for built-in regdb").
Revert the addition of db.txt so it will be possible to
do a clean revert of this commit and restore the feature.

Change-Id: Ic4000ec52339d9f9d70f561ceaea8befcf5ac871
Signed-off-by: Lior David <liord@codeaurora.org>