Add RSS to dumpsys meminfo

Include the RSS info into the meminfo output of dumpsys and
incident_report.

Bug: 117880513
Test: adb shell dumpsys meminfo
Test: cts-tradefed run cts-dev --module \
      CtsIncidentHostTestCases --test \
      com.android.server.cts.MemInfoIncidentTest
Change-Id: Id1058e279b7ca6925b59a6a523e0f0d14d830761