Remove adb.network.port label

Good old "ADB over network" feature is no more.

Change-Id: If76b0114a3cc9738663e24c4750b1519784b4969
diff --git a/common/private/property_contexts b/common/private/property_contexts
index e8411b7..c9f72e7 100644
--- a/common/private/property_contexts
+++ b/common/private/property_contexts
@@ -1,3 +1 @@
-adb.network.port                       u:object_r:system_prop:s0
-
 ro.telephony.use_old_mnc_mcc_format    u:object_r:exported3_default_prop:s0