Case finished without waiting for hal result

In VTS case RadioNeteworkTest#setEmergencyMode,
Case finishes without waiting for the result of exitEmergencyMode.
When the response is back, destroyed mutex will be used,
It will lead case end abnormally.

So, waiting for the response of exitEmergencyMode is necessary.

Bug: 352533464
Test: run VTS case RadioNetworkTest#setEmergencyMode
(cherry picked from https://googleplex-android-review.googlesource.com/q/commit:80f66789017ed8c3b3b9d038f67446f58d80ea60)
Merged-In: I52c527195b71e112275d74c80d0f9c91e42b3041
Change-Id: I52c527195b71e112275d74c80d0f9c91e42b3041