Add log and dump for dnsResolver service

Use log callback from netd server to print binder log.
Also add dump functionality.

blueline:/ # dumpsys dnsresolver
NetId: 100
  DNS servers: # IP (total, successes, errors, timeouts, internal errors, RTT avg, last sample)
    2001:4860:4860::8844 (1, 1, 0, 0, 0, 15ms, 5195s)
    2001:4860:4860::8888 <no data>
    8.8.8.8 <no data>
    8.8.4.4 <no data>
  No search domains defined
  DNS parameters: sample validity = 1800s, success threshold = 25%, samples (min, max) = (8, 64), base_timeout = 5000msec, retry count = 2times
  DNS64 config: none
  Private DNS mode: OPPORTUNISTIC
  Private DNS configuration (4 entries)
    8.8.4.4 name{} status{success}
    8.8.8.8 name{} status{success}
    2001:4860:4860::8844 name{} status{success}
    2001:4860:4860::8888 name{} status{success}
  Concurrent DNS query timeout: 0


Bug: 126141549
Test: built, flashed, booted
      system/netd/tests/runtests.sh pass
      Verified that log is shown in both "dumpsys netd"
      and "dumpsys dnsresolver"

Change-Id: I06382f811343f3dd52f246da5c5e03b70eeda0e1