Remove two remaining unnecessary direct dependencies on rootrflx

[wmtan]

Since virtually everything has an indirect dependency on rootrflx through DataFormats/Math or DataFormats/DetId, Giulio recently removed explicit link dependencies on rootrflx from many BuildFiles so as to remove BuildFile differences between CMSSW_7_4_X and CMSSW_7_4_ROOT6_X. I discovered two additional BuildFiles in which this explcit dependency can be removed.

[cmsbuild]

A new Pull Request was created by @wmtan for CMSSW_7_4_X.

Remove two remaining unnecessary direct dependencies on rootrflx

It involves the following packages:

DataFormats/TrackingRecHit
SimDataFormats/Associations

The following packages do not have a category, yet:

SimDataFormats/Associations

@cmsbuild, @cvuosalo, @nclopezo, @slava77 can you please review it and eventually sign? Thanks.
@makortel, @VinInn this is something you requested to watch as well.
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@Degano you are the release manager for this.
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[slava77]

@cmsbuild please test

I also made cms-sw/cms-bot#387 to resolve the new-package-pending

[cmsbuild]

The tests are being triggered in jenkins.

[cmsbuild]

+1
Tested at: 4a54959
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-8281/3410/summary.html