The regdom intersection code simply tries intersecting
each rule of the source with each rule of the target.

Since the resulting intersections are not observed
as a whole, this can result in multiple overlapping/duplicate
entries.

Make the rule addition a bit more smarter, by looking
for rules that can be contained within other rules,
and adding only extended ones.
Signed-off-by: Eliad Peller <eliad@wizery.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>