init.rc: Restored TCP performance tuning

This patch tunes the TCP buffer sizes for high
performance data links including global max rmem
and wmem.

Change-Id: I78dc92bc8190883686678230b0a34a8e32507fa5
CRs-Fixed: 439205 435908
ueventd.rc: Change owner of graphics drivers to system

iWifi Display service needs permission to open these drivers.

Change-Id: I1d9e4ae372f09ecf4104888a9910d09903d892d1
(cherry picked from commit f087420bf5eada3017e107a3a8da4e74f683da18)
(cherry picked from commit 1b3f9226cd3ad681a0ef08038d874921ca62ee4c)
(cherry picked from commit 5b4becc1b814b0f9e96d4f3aaec380d74f4b0739)
Add required permissions and files for data

 - Add /data/radio
 - Set gateway property after DNS
 - Allow radio users to set properties associated with
   all rmnet interfaces. Not just rmnet0

Change-Id: Ia60fcb8f90aa73ffd40e839b93356ee50a9e5072
ADB: Don't force -O2 if something else is provided instead.
C++11 fixes.