CEC: Add implementation of getCecVersion method to default HdmiCec

Bug: 185434120
Test: manual
Change-Id: I019cb5cf68e73331b1468b60cbfb95be7a052522
diff --git a/tv/cec/1.0/default/HdmiCecDefault.cpp b/tv/cec/1.0/default/HdmiCecDefault.cpp
index b5f2ba7..4bc5ef3 100644
--- a/tv/cec/1.0/default/HdmiCecDefault.cpp
+++ b/tv/cec/1.0/default/HdmiCecDefault.cpp
@@ -113,7 +113,7 @@
 }
 
 Return<int32_t> HdmiCecDefault::getCecVersion() {
-    return 0;
+    return property_get_int32("ro.hdmi.cec_version", CEC_OP_CEC_VERSION_1_4);
 }
 
 Return<uint32_t> HdmiCecDefault::getVendorId() {