Move adbd from root to system

Bug: 63910933
Test: normal boot sailfish, checks adb works
Test: recovery boot sailfish, checks adb works
Test: normal boot bullhead, checks adb works
Test: recovery boot bullhead, checks adb works

Change-Id: I1b27910c06a4172ca718b3344736ec8e3429f477
Merged-In: I1b27910c06a4172ca718b3344736ec8e3429f477
(cherry picked from commit 93defc17f376041437e5157a7c4d9e0344441811)
diff --git a/rootdir/init.usb.rc b/rootdir/init.usb.rc
index 915d159..3168f40 100644
--- a/rootdir/init.usb.rc
+++ b/rootdir/init.usb.rc
@@ -12,7 +12,7 @@
     mkdir /data/adb 0700 root root
 
 # adbd is controlled via property triggers in init.<platform>.usb.rc
-service adbd /sbin/adbd --root_seclabel=u:r:su:s0
+service adbd /system/bin/adbd --root_seclabel=u:r:su:s0
     class core
     socket adbd stream 660 system system
     disabled