Allow adbd to access /proc/net/{tcp,tcp6,udp,udp6}

File accesses go through com.android.ddmlib.SyncService for CTS
ListeningPortsTest.

Bug: 193151739
Test: atest ListeningPortsTest
Change-Id: I0c66fb5e35cda3b1799cf003402e454d7a951e96
Merged-In: I0c66fb5e35cda3b1799cf003402e454d7a951e96
1 file changed