Allow system server to read car_bootuser_prop

Bug: b/131595044
Bug: b/130297788
Test: Local build
Change-Id: I1a15816cfd42eeab3b34d84eeb6e4aa7d4da814f
(cherry picked from commit 7d83b97f6d7651fb8b17875f653ac754b74ad416)
1 file changed