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)
Expose /dev/hw_random to group "system".

This is needed to let EntropyMixer (runs inside system_server) read
from /dev/hw_random.

Change-Id: Ifde851004301ffd41b2189151a64a0c5989c630f
ueventd: Add rules for governors and cpufreq

This change requires a kernel patch in cpufreq to work.

Change-Id: I6281645291ca4516748f65d0799e14971c5fb2ea
System/core: Start qrng daemon upon power up

1. Set root permissions to qrng daemon upon powerup
2. Drop all permissions except few, just enough to make ioctl calls

Permission for hardware random device is changed in
this gerrit (part of Point 1(above))

Change-Id: Ibf58b7212ba1ec532de9d461266081f3ac4395e3
Signed-off-by: Hariprasad Dhalinarasimha <hnamgund@codeaurora.org>