Assumption check should not affect ethernet enabled state

setEthernetEnabled() is used as a synchronization mechanism, so don't
let it affect enabled state.

Test: TH
Flag: EXEMPT test
Bug: 10000001
Change-Id: Ib023b7f944a8a84435dcc546aced9b0eab96d364

tests/cts/net/src/android/net/cts/EthernetManagerTest.kt

@@ -631,8 +631,8 @@ class EthernetManagerTest {
             // tethering.
             releaseTetheredInterface()
             // Force releaseTetheredInterface() to be processed before proceeding by calling
-            // setEthernetEnabled(true) which always waits on a callback.
-            setEthernetEnabled(true)
+            // setEthernetEnabled() which always waits on a callback.
+            setEthernetEnabled(ethernetEnabled)
         }
     }