broadcastradio@2.0 VTS uses DAB frequency invalid in some regions

DAB frequency 178352kHz hardcoded in the test is used in EU region
(channel 5C) but it is not valid in others (e.g. Korea and China).

Therefore DabTune test was modified to use one of supported
frequencies reported via getDabRegionConfig method.

Test: run VtsHalBroadcastradioV2_0TargetTest on hardware units
configured for Europe, China and Korea DAB tuner regions.

Bug: b/190136847

Change-Id: Icd71e42a9242528465ac1358465d8b6d6d4896bf
diff --git a/broadcastradio/2.0/vts/functional/VtsHalBroadcastradioV2_0TargetTest.cpp b/broadcastradio/2.0/vts/functional/VtsHalBroadcastradioV2_0TargetTest.cpp
index 362ab41..615fde0 100644
--- a/broadcastradio/2.0/vts/functional/VtsHalBroadcastradioV2_0TargetTest.cpp
+++ b/broadcastradio/2.0/vts/functional/VtsHalBroadcastradioV2_0TargetTest.cpp
@@ -496,10 +496,26 @@
  *  - program changes exactly to what was requested.
  */
 TEST_P(BroadcastRadioHalTest, DabTune) {
+    Result halResult;
+    hidl_vec<DabTableEntry> config;
+    auto cb = [&](Result result, hidl_vec<DabTableEntry> configCb) {
+        halResult = result;
+        config = configCb;
+    };
+    auto hidlResult = mModule->getDabRegionConfig(cb);
+    ASSERT_TRUE(hidlResult.isOk());
+
+    if (halResult == Result::NOT_SUPPORTED) {
+        printSkipped("DAB not supported");
+        return;
+    }
+    ASSERT_EQ(Result::OK, halResult);
+    ASSERT_NE(config.size(), 0U);
+
     ASSERT_TRUE(openSession());
 
     ProgramSelector sel = {};
-    uint64_t freq = 178352;
+    uint64_t freq = config[config.size() / 2].frequency;
     sel.primaryId = make_identifier(IdentifierType::DAB_FREQUENCY,freq);
 
     std::this_thread::sleep_for(gTuneWorkaround);