Mark more NQE histograms as deprecated

These network quality estimator histograms were deprecated earlier,
but they were not correctly marked as deprecated.

Bug: 843210
Change-Id: Ie852a015072a4734c02c7cd2fd6d03fb35bf5f95
Reviewed-on: https://chromium-review.googlesource.com/1063552Reviewed-by: Gayane Petrosyan <gayane@chromium.org>
Commit-Queue: Tarun Bansal <tbansal@chromium.org>
Cr-Commit-Position: refs/heads/master@{#561357}

tools/metrics/histograms/histograms.xml

@@ -115862,6 +115862,9 @@ uploading your change for review.
 </histogram_suffixes>
 
 <histogram_suffixes name="NQE.NetworkTypes" separator=".">
+  <obsolete>
+    Deprecated 01/2018.
+  </obsolete>
   <suffix name="2G" label="On 2G network"/>
   <suffix name="3G" label="On 3G Network"/>
   <suffix name="4G" label="On 4G network"/>