SurfaceFlinger: migrate capabilities to surfaceflinger.rc

SurfaceFlinger requires CAP_SYS_NICE which is set in
libcutils/fs_config.cpp. This is the old way of setting capabilities
and new the way is to set it directly on surfaceflnger.rc

Test: adb shell /data/nativetest64/SurfaceFlinger_test/SurfaceFlinger_test
Test: adb shell stop surfaceflinger && adb shell start surfaceflinger
Bug: 147271477
Change-Id: I680509a385928a9c929d4fe4857118af219e2b13
diff --git a/services/surfaceflinger/surfaceflinger.rc b/services/surfaceflinger/surfaceflinger.rc
index aea602b..d3942e8 100644
--- a/services/surfaceflinger/surfaceflinger.rc
+++ b/services/surfaceflinger/surfaceflinger.rc
@@ -2,6 +2,7 @@
     class core animation
     user system
     group graphics drmrpc readproc
+    capabilities SYS_NICE
     onrestart restart zygote
     writepid /dev/stune/foreground/tasks
     socket pdx/system/vr/display/client     stream 0666 system graphics u:object_r:pdx_display_client_endpoint_socket:s0