emulator: not start adbd upon ro.kernel.qemu=1

clean up emulator specific rules.

BUG: 72900827

Change-Id: Ica60838562fd773bcde5752c11586183ce55b71a
diff --git a/rootdir/init.usb.rc b/rootdir/init.usb.rc
index 3168f40..f0681d2 100644
--- a/rootdir/init.usb.rc
+++ b/rootdir/init.usb.rc
@@ -18,10 +18,6 @@
     disabled
     seclabel u:r:adbd:s0
 
-# adbd on at boot in emulator
-on property:ro.kernel.qemu=1
-    start adbd
-
 on boot
     setprop sys.usb.configfs 0